Lightness depends on the amount of air incorporated, on the expansion of that air, and on the presence of baking powder.

If the materials used are cold and the manipulation is carried on in a cold room, or if the paste is chilled by being placed in a refrigerator, the expansion of the inclosed air is greater during the baking process.

Flakiness results when the ingredients are so mixed as to make layers. To accomplish this, fat is not thoroughly mixed into the dry ingredients, but is left in pieces by being cut in with a knife or rubbed in with a spoon.

Tenderness depends on the relative amounts of fat and water used and on the manipulation. The more fat and the less water used, within limits, the tenderer will be the crust. Handling the paste develops elasticity by developing gluten, and so makes a tough crust. If the fingers are used to mix the fat with the flour, the heat of the fingers melts the fat and causes it to act as liquid; thus more flour is required, which tends to make a tough paste.