Stacey's handshake-worthy pudding earned Paul's praise for being 'light, moist, and properly cooked throughout.' The foundation of that lightness begins with properly creaming butter and sugar—a full five minutes on medium-high speed, not the cursory minute many home bakers give it. During this time, you're incorporating millions of tiny air bubbles that will expand during cooking, creating lift. The mixture should transform from dense and yellow to pale, fluffy, and almost white. This step cannot be rushed or shortcuts taken; the texture of your finished sponge depends entirely on the air you trap at this stage.