Who would have thought that the secret to even heat while grilling would be as simple as placing an aluminum pan inside of the grill? While some experts swear by putting an empty pan in the grill in order to catch drips and prevent flare-ups, we take it a step further: We not only put a pan in the grill but also fill it with water. Why? Because placing a pan of water opposite the coals lowers the heat inside a grill, allowing you to cook more slowly and gently, with more uniform cooking.
But after doing this for many years, it occurred to us that we weren’t sure which component—the water or the pan—was more responsible for the benefits. So, in true Cook’s Illustrated fashion, we ran a few tests to find out.
We gauged the heat disparities on three different grill setups by running a toast test. We built indirect fires in each grill and then placed a disposable aluminum pan opposite the coals in one, an aluminum pan filled with 3 cups of water in another, and nothing in the third grill. We let the coals burn for 15 minutes and then spread six slices of bread over each grill’s cooler side and let them cook for 4 minutes.
Bread toasted on the grill without a pan turned dark brown and the pieces closest to the coals burned, while the slices cooked on the two grills with aluminum pans were lightly and evenly tanned. The bread toasted over the water-filled pan was slightly paler, but not by much. The grill temperatures correlated with the toast results: The grill without the pan registered 415 to 425 degrees, the grill with the empty pan 385 to 395 degrees, and the grill with the water-filled pan 375 to 385 degrees.
When we didn’t put an aluminum pan in the grill, the bread showed fierce, spotty heat chars:
When grilling with a pan (with or without water in it), the moderate, even heat lightly toasted the bread:
Even putting an empty aluminum pan in the grill will significantly drop its temperature. Aluminum is very efficient at absorbing heat, allowing it to lower the temperature inside the grill by about 30 degrees and to even out hot spots. Water added to the pan captures more heat, helping drop the temperature even further, but it’s mainly the metal pan that’s responsible for the change. So if you ever put an empty pan in the grill to catch drips, be aware that it will lower the temperature as well.
RECIPE FOR MEMBERS: Sweet and Tangy Barbecued Chicken
We’ve all had terrible grilled chicken: Pieces with burnt skin, parched meat, and a coat of sweet, goopy sauce. But now that you know the secret to keeping the heat even in your grill, this tangy-sweet glazed barbecued chicken will always be perfectly cooked.