Q: How much is “one shallot”? In my experience, shallots vary widely in size, from 1/4 cup to 1/2 cup in size.
A: Nature is never uniform, which is part of the fun – and challenge – of cooking with things that grow in nature. Recipe writers ought to include an equivalent (“1 ear of corn, or 1/2 cup kernels.”) My apologies, as a recipe writer, if I don’t do that often enough.
Not only do shallots vary in size, but they also sometimes split into lobes, leading cooks to wonder if they should use both sections. It depends on the recipe and how much it yields. Try to visualize that to decide whether a whole shallot will be more than your dish can hold. In general, a large shallot yields about 1/2 cup diced, a medium one (or a single large lobe) yields 1/4 cup, and a small one (or small lobe) is about 2 tablespoons.