How we tested
The must-have kitchen appliance in European and Australian households isn’t an Instant Pot, a Vitamix blender, or even a gleaming KitchenAid stand mixer—it’s a Thermomix all-in-one kitchen machine. Thermomix is the pioneering brand of this countertop appliance, but there are now many competitors making all-in-one machines. These gadgets look like food processors and are equipped with heating elements and a plethora of attachments for stirring, steaming, kneading, measuring, weighing, grinding, and more. The promise is bold: one machine to replace every small appliance in your kitchen. Fans of these machines claim you can use one to cook an entire multicourse meal, including recipes such as hands-off risotto with a steamed fish fillet, warm dip with a side of pita bread, and linguine with steamed mussels and a slow-simmered tomato sauce.
These machines have been embraced in the kitchens of Michelin-starred restaurants such as Noma, El Bulli, and the French Laundry. Heston Blumenthal purchased 15 Thermomix machines for his Michelin-starred Fat Duck, and Wylie Dufresne reportedly used one to make his famous hollandaise sauce because it allowed him to dial in a precise temperature and control the speed and frequency of stirring. Massimo Bottura, chef of Osteria Francescana (consistently named one of the top restaurants in the world), has a partnership with the manufacturer of another all-in-one machine, HotmixPRO, and reportedly uses his for everything from grating Parmesan to making dough to emulsifying sauces.
In European and Australian home kitchens as well as professional kitchens, these machines are already essentials. Do they have a place in American home kitchens?
What Does an All-in-One Machine Look Like?
While the promise of “one kitchen appliance to rule them all” sounds appealing, it comes at a hefty price: The contenders in our lineup ranged in price from about $395 to nearly $1,985. While dozens of models exist in Europe and Australia, we considered only the machines that were compatible with North American electrical outlets, leaving us with a total of five models, all sharing the same set of functions: cooking, blending, processing, and mixing. We tested two machines from Thermomix, the more basic TM5 and the recently released TM6, which offers additional functions for slow cooking, boiling water, making caramel, and sous vide cooking.
All the machines in our lineup are about the same size as a stand mixer and share a similar design: a workbowl that sits atop a base containing a concealed heating element and motor. Inside each workbowl is a blade for chopping and mixing. Every machine in our lineup came with an assortment of attachments, including steamer baskets, spatulas, and interchangeable blades.
Each machine also came with its own recipes either programmed into it or printed in a separate booklet. Our first set of tests focused on three recipes (each representing a different functionality) that all the machines could prepare: risotto, hollandaise sauce, and basic bread or pizza dough (one machine did not have a recipe for bread dough). We then pitted each machine against the equipment they promised to replace—our favorite food processor, blender, and stand mixer, as well as our stovetop—in a battery of tests: chopping carrots, onions, and celery for mirepoix; emulsifying eggs and butter for hollandaise sauce; making our Almost Hands-Free Risotto and Pasta e Ceci recipes; pureeing raw kale, frozen pineapple, and orange juice into smoothies; and kneading our tough Bagel Bread dough.
Before we get into how well these machines performed, we have to note that the biggest problem we encountered was that they promised ease but were frustratingly difficult to use. We encountered usability issues with nearly every machine, even when following the instructions and recipes that came with them.
First, the workbowls of the machines are almost entirely enclosed and not see-through. Every workbowl has a small peephole that allowed us to add ingredients and watch the food without interrupting the machine as it worked; however, we found that these holes were too small to be useful. Because of this, every time we wanted to check the food, we had to stop the machine, unlock the lid, and then resume the task. Worse, one machine’s plastic lid was so tight that we had to pry it on and off with both hands. Its manufacturer says that the lid should loosen over time, but it didn’t for us, even after weeks of use.
Second, to operate many of the machines, we had to frequently refer to their user manuals. One machine had vaguely named programmed settings, such as P2 Simmer, P3 Simmer, and P2 Braise. Another machine’s recipes were displayed ticker tape–style on the front of the machine; if we missed a step or ingredient, it was impossible to go back, so we had to restart the text scroll all over again.
Finally, all the machines were challenging to clean. Depending on the recipe, we’d finish cooking and have up to 10 components from each machine to wash. While most of the machines’ components are dishwasher-safe, we had to remove any rubber lid gaskets and metal blades beforehand. This wasn’t a deal breaker, but it made cleanup more complicated.
Built-In Recipes Worked Best
When we relied on each machine’s recipes, we were able to produce, for the most part, great food, including risotto with creamy, intact grains of al dente rice. Bread dough came together quickly, and one machine even had a helpful warming option for proofing (the others called for transferring dough to a bowl and proofing on the countertop). However, all the machines failed when we made hollandaise sauce. Three made sauces that were much too thin, and two machines ran too hot and produced sauces with the consistency of scrambled eggs.
That said, the two Thermomix machines had additional features that made them easier to use than the other all-in-one machines. Both had color touch screens (the TM6 has a slightly bigger screen) that clearly showed the programmed recipes and walked us through them step by step. We also didn’t need measuring cups or a separate scale to portion ingredients ahead of time because each machine had a built-in scale.
All-in-One Machines as Stand Mixers and Food Processors
To see how our own recipes fared, we started by making Bagel Bread dough in each of the machines and compared the results to the same dough made in our favorite inexpensive stand mixer, the KitchenAid KSM75WH Classic Plus Series 4.5-Quart Tilt-Head Stand Mixer. All the machines were able to knead the tough dough, and the finished bread was indistinguishable from dough kneaded in the KitchenAid. The recipe calls for kneading the dough for 10 minutes, so we appreciated the machines that were equipped with built-in timers. All in all, the machines were just as easy to use as the stand mixer, so we considered this a win.
Next, we used the machines to prep mirepoix; grate Parmesan cheese for risotto; and cut up vegetables, mince pancetta, and puree tomatoes for pasta e ceci and compared the results to the same tasks performed in our top-rated food processor, the Cuisinart Custom 14 Cup Food Processor. Dicing the vegetables for mirepoix took some trial and error (and referencing user manuals), as we needed to find the right speed on each machine. Lower speeds simply stirred the vegetables, while higher speeds liquified them into juice. In the end, all the machines were able to produce relatively even dices that were comparable to the dice produced by the Cuisinart.
However, in terms of usability, none of the machines came close to the simplicity of the Cuisinart. One of the things we love about our top-ranked food processor is its clear workbowl, which allowed us to see the progress we were making when dicing the vegetables. Since the all-in-one machines’ workbowls and lids aren’t clear, we had to remove the lid every couple of seconds to monitor progress. We often overshot it, leading to overprocessed vegetables. Adding to this lack of precision was the fact that two of the five all-in-one machines didn’t have a pulse button.
Finally, none of the machines in our lineup came with attachments for shredding or slicing. We like to use the shredding and slicing disks on the Cuisinart to quickly shred brussels sprouts for salad or uniformly slice potatoes for gratin. Overall, the food processing capabilities of these machines were OK, but we much prefer using the Cuisinart.
Cooking in All-in-One Machines
Next, we tried cooking our recipes for Pasta e Ceci and Almost Hands-Free Risotto with Chicken and Herbs in all the machines and compared the results to the same recipes cooked in a Dutch oven on the stovetop. We struggled to adapt our recipes to the machines. First, most conventional recipes call for heat levels such as “medium” or “medium-low,” but the machines required us to specify an exact temperature, so we had to guess temperatures for sautéing and simmering. Second, most of the machines won’t operate without their spinning blades in place; subsequently, all but one of the batches of risotto ended up with small pieces of bone from the bone-in chicken breasts. Even when set to the lowest stirring mode, the blades of a few of the machines even cut through tender pasta and rice. This constant mixing action also meant that chicken skin and vegetables didn’t fully brown because they didn’t spend enough time in contact with the hot bottom of the workbowl, resulting in dishes that were lighter in color and weaker in flavor than the risotto and pasta we made on the stovetop.
The All-Clad Prep&Cook performed best at cooking our adapted recipes. One reason for this is its larger cooking surface. A larger cooking surface allows for more contact between the food and the cooking surface, resulting in better browning and more even cooking. We measured the widths of the flat cooking surfaces of all the machines and found that they ranged from 4 inches to 6 inches, with the All-Clad having the widest cooking surface in the lineup. The All-Clad model was also the only machine with a blade that could be removed during cooking, so food remained intact as we browned it.
All-in-One Machines as Blenders
While wider workbowls may have been an advantage for browning, they were a hindrance to blending. The same All-Clad machine that we liked for cooking could not make a decent smoothie. While most models were equipped with a vertical blade similar in shape to the blade in a traditional blender, the All-Clad had a flat blade that resembled a food processor blade. When making a smoothie in this machine, ingredients got trapped under the blade and ended up unprocessed, no matter how long we blended. What’s more, bits of kale and pineapple were pushed to the edges of the All-Clad’s wide workbowl, where they stuck to the wall, just out of reach of the spinning blades. Only the two Thermomix machines made smoothies that rivaled the smoothies made in our favorite midpriced blender; their conical workbowls helped keep ingredients moving toward the blade.
Evaluating Additional Features on the Thermomix TM6
At the end of testing, the two Thermomix machines distinguished themselves from the rest of the pack at basic processing, blending, cooking, and mixing tasks. Both the Thermomix TM5 and the Thermomix TM6 performed identically through our main cooking tests, which isn’t surprising since the hardware of the machines is practically identical. However, the TM6 comes with a significant software upgrade that offers additional features, such as the ability to slow-cook, heat water to a specific temperature, cook sous vide, make yogurt, and set precise sugar stages for caramel.
We tried all these additional settings with limited success. The kettle and sous vide functions were both inadequate; the water fell short of the temperature we programmed by 5 to 10 degrees and never fully boiled on the kettle setting. Our sous vide eggs were underdone. Slow cooking also was a bust: The machine won’t operate unless the blade is in place and stirring, so over the 7-hour cooking time, it pureed the potatoes and carrots and shredded the meat in our beef stew. (Thermomix hasn’t released any recipes for its slow-cooker setting, so we couldn’t evaluate how it would fare with its own recipes.) The one success was the Thermomix’s recipe for caramel using the sugar-stages setting. Caramel and sugar work are notoriously tricky—daunting even to experienced cooks—but the Thermomix turned out a perfectly golden caramel that was almost completely hands-off. It even has a special cleaning stage that heats water and mixes it at high speed, so we didn’t have to contend with scraping hardened caramel from the workbowl.
Should You Buy an All-in-One Machine?
If you’re thinking of purchasing one of these machines to replace a bevy of small appliances, keep in mind that our top-rated food processor, midpriced blender, and stand mixer combined cost about half of what the best all-in-one machine in our lineup costs. In addition, those three appliances perform better and are easier to use. All-in-one machines also fall short of being truly all-in-one: They don’t slow-cook or cook sous vide effectively, and they struggle with basic tasks such as browning food and boiling water. Finally, they work best with their own recipes, and adapting outside recipes to the all-in-one machines takes planning and creativity.
Even so, an all-in-one machine can be a key asset in small kitchens or in situations where kitchen space is nonexistent, such as on a boat, in an RV, or in some dorm rooms. Here, a good model with a 1-foot-square footprint can offer the convenience of many appliances and an opportunity to create home-cooked meals where it might not be possible otherwise. They’re also a good option for those looking to build confidence in the kitchen with guided cooking; our favorite machine has an extensive recipe collection and walks you through recipes step by step. All-in-one machines can also be useful for some precision tasks such as candy making if you choose to follow their recipes.
Our takeaway: These machines are good at certain tasks and not very good at others. We can recommend the Thermomix TM6 to those interested in small-space cooking, guided cooking, cooking that requires holding temperatures (with a little bit of tinkering), or sugar work. But if you're considering buying one of these machines to replace a bunch of different appliances and value performance over space constraints, we do not recommend them. Of the machines we tested, the TM6 and TM5 both performed best at processing, blending, and cooking. Though we didn’t find the TM6’s extra settings to be all that useful, it’s currently priced only about $50 more than the TM5, which we think is worth paying for the larger display, thousands of built-in recipes, and sugar-stages setting, which made caramel with ease.
The Best All-in-One Machine: The Cuisinart Complete Chef Cooking Food Processor
We recently tested Cuisinart’s answer to the Thermomix all-in-one machine, the Cuisinart Complete Chef Cooking Food Processor (about $700), running the same tests. Our surprising conclusion? It’s terrific, both as a food processor and multipurpose mixing and cooking machine. At about half the price of the top-rated Thermomix, it’s well worth considering. Unlike the Thermomix, you can remove all the blades for cooking, so you can make delicate foods without inadvertently pureeing them, or you can choose a stirring paddle with six speeds, including intermittent stirring. Its clear cooking lid provides visibility to monitor progress, unlike most of the all-in-one machines we tested. With about 200 recipes built in and a USB port for potential updates, as well as easy-to-use manual cooking and food processing settings, the Complete Chef was a pleasure to use and easy to clean, by hand or in the dishwasher. We also liked its sturdy stainless-steel workbowl. This machine excelled in all our tests, with one exception: It wasn’t very good at blending, so it produced thin, watery smoothies with flakes of kale and small chunks of pineapple.
- Five models priced from about $385 to nearly $1,985
- Cook the risotto recipe from each machine’s recipe book
- Cook our recipe for Almost Hands-Free Risotto with Chicken and Herbs and compare the results with the same recipe prepared on the stovetop
- Cook our recipe for Pasta e Ceci and compare the results with the same recipe prepared on the stovetop using ingredients processed in our favorite food processor
- Dice vegetables for mirepoix and compare the results with the same ingredients processed in our favorite food processor
- Process raw kale, frozen pineapple, and orange juice into smoothies and compare the results with the same ingredients processed in our favorite midpriced blender
- Prepare the hollandaise sauce recipe from each machine’s recipe book
- Prepare our recipe for Foolproof Hollandaise Sauce and compare the results with the same recipe made on the stovetop
- Program the machines to hold the hollandaise sauce at 145 degrees for 1 hour, checking for curdling or breakage
- Prepare either basic sandwich bread dough or pizza dough from each machine’s recipe book and evaluate the results after baking
- Prepare our recipe for Bagel Bread and compare the dough with the same recipe made in our top-rated stand mixer; evaluate the breads after baking
- Evaluate the size of the workbowls and the setup, controls, interface, comfort, and ease of operation of the machines
- Clean the machines according to the manufacturers’ instructions after every test
- Boil water on the kettle setting (TM6 only)
- Prepare beef stew from Multicooker Perfection using the slow-cooker setting (TM6 only)
- Soft-boil eggs using the sous vide setting (TM6 only)
- Prepare the machine’s recipe for yogurt using fermentation setting (TM6 only)
- Prepare the machine’s recipe for caramel using sugar-stages setting (TM6 only)
Ease of Use: We considered how easy the machines were to operate.
Food Processor: We looked at how well the machines could process food compared with our top-rated food processor.
Blender: We evaluated how well the machines blended compared with our top-ranked midpriced blender.
Stand Mixer: We compared each machine’s ability to make bread dough with our favorite inexpensive stand mixer.
Heating and Cooking: We evaluated how well each machine could make fully cooked, well-browned food within recipe times.
Cleanup: We rated how easy the machines were to clean.