Bulging Brownies

• When the heat of the oven hits brownie batter, tiny air pockets expand and cause the batter to bulge. This is normal and unavoidable, but if your batter puffs up like a cake, take a closer look at your recipe. Brownie recipes vary widely, and some include chemical leaveners such as baking soda or baking powder, which cause them to rise during baking. Technique also influences the final result: vigorous beating works more air into the batter, causing more air pockets to form and then expand in the heat of the oven.

Chewy Brownies

• You can ensure a dense, chewy brownie if you use the right ingredients. Aside from skipping the chemical leaveners, one of the most important factors in getting the right texture is the ratio of saturated fat to unsaturated fat -- specifically, the ratio of butter to oil. For satisfyingly chewy brownies, a 1-to-3 ratio is ideal. Replacing some of the oil with egg yolks helps avoid this oil greasiness without upsetting the final results.

Cakey Brownies

• If you prefer a cakelike brownie -- moist but lighter than a chewy brownie -- look for a recipe that uses less butter, as well as a chemical leavener. Most recipes call for baking powder, which works better with chocolate than baking soda. One exception occurs if you are using Dutch-process cocoa, in which case baking powder is the preferred leavener. Recipes for cakey brownies also rely on certain techniques to incorporate more air into the batter, such as creaming the butter and sugar as you would for a cake -- rather than melting the butter -- and whipping the batter.

Crusty Brownies

• A particular subset of brownie enthusiasts pays less attention to the texture of the brownie than to the appearance -- specifically, that paper-thin, crustlike top layer that some brownies exhibit. Just as dense brownies or cakey brownies are not left to chance, brownies with this crunchy feature are no accident. This time the object is to beat the batter into oblivion after the eggs are added, which results in a layer of meringue in the finished product. Chewy brownie lovers, be forewarned: this technique will likely leave you with a slightly cakey result.