“Like flours, not all fats are created equal. Oil is fat that is liquid at room temperature but good pastry cannot be made with oil. Flour simply absorbs the oil and the resulting dough is mealy, not tender and flaky. The ideal fat for pastry-making is one with a high melting point because the longer it takes for the fat to melt, the longer it keeps the little parcels of dough separate, generating little packets of steam to puff and lighten the dough. Pig fat (lard) has a high melting point and very little water content, so is ideal on both counts.”