Understand what actually happens when you bake. Start with the question everyone asks — baking soda is pure sodium bicarbonate and needs an acid (buttermilk, brown sugar, cocoa) plus heat to make the gas that lifts your batter, while baking powder already carries its own acid, so it works alone, and double-acting powder gives a second lift in the oven. Then go deeper: how gluten forms and why bread flour chews while cake flour stays tender; why creaming butter aerates but melted butter makes cookies spread; how sugar and fat tenderize; what eggs really do; and how starch gelatinization sets the crumb (and retrogradation stales it). The hardest questions reach real food chemistry — chocolate tempering, meringue stability, lamination. Every explanation names the principle, the classic mistake, and a rule you keep. Skill practice, not a test of intelligence.