Steam, not sugar, is what first decides the fate of a raspberry tart shell. When a filled tart goes straight into the oven, water from the fruit and custard races into the raw dough before its structure has set, driving uneven expansion and a soggy, leathery crumb. Blind‑baking the empty shell changes the thermodynamics of that equation long before the raspberries arrive.In the first bake, heat dr...More