This question came up over a so-called red velvet muffin. With its dainty dab of frosting and seductive vanilla-cocoa fragrance, this bakery item seemed for all the world like a cupcake. In what way, exactly, did it deserve the name muffin?
Classic, familiar muffins—the corn or blueberry ones that nobody suspects of being cupcakes—are often made using a mixing method called the muffin method. The combined liquid ingredients, including melted butter or another liquid fat, are mixed into the combined dry ingredients just enough to make a batter; lumps in the batter translate into a somewhat coarse, breadlike crumb when the muffins are baked. (Often—not always—the batter is coaxed into a bulging, overflowing top by baking at a higher temperature than other baked goods.)
Cupcakes (like cakes) are commonly made using the “creaming method”: Solid fat and sugar are combined, trapping some air; then dry and liquid ingredients are added, producing a finer, more delicate crumb.
Seems like a reasonable rule of thumb; simply ask the baker how the baked good was made, and if it was the muffin method, you can be confident you’re eating a muffin. If the baker’s already left for the day though, is it safe to judge by the texture?
Maybe not. As baking expert Paula Figoni writes in How Baking Works, “muffins are often mixed using the muffin method” but “[the] creaming method produces lighter muffins with the finer crumb of a cake.” So if some muffins are made using non-muffin mixing methods, is there a hard-and-fast rule? Perhaps we can simply trust our instincts: if it has the sweet richness of a cupcake, the tender, compact dome of a cupcake, might it still be a muffin?
Personally, I stand by the elegant and simple rule presented in Joseph Amendola’s book Understanding Baking: “If it is too rich to tolerate a pat of butter, it’s not a muffin.”