Tenderness

Tenderness depends mostly on how much gluten develops. Fat coats flour proteins and keeps them from linking, sugar holds on to water that gluten would otherwise use, and low-protein flours such as cake flour form weaker gluten. Gentle, brief mixing after the flour goes in also helps.

Too much tenderness can be a problem: a cake with too much fat or sugar may crumble or sink. Good recipes balance tenderizers with structure builders such as flour and eggs.