Use fruit that is flavourful and firm enough to keep some structure during baking. Cut pieces to a reasonably consistent size so they soften at a similar rate. Frozen fruit can work well but may release more liquid; follow a recipe written for it or adjust with care.
Select and prepare fruit
Use fruit that is flavourful and firm enough to keep some structure during baking. Cut pieces to a reasonably consistent size so they soften at a similar rate. Frozen fruit can work well but may release more liquid; follow a recipe written for it or adjust with care.
Balance sweetness and acidity
Fruit varies by season and variety. Sugar should support the fruit rather than hide it, while lemon juice or another mild acid can sharpen a flat filling. Taste raw fruit before adding sugar, but never taste a filling that contains raw flour.
Choose a thickener
Flour, cornstarch, tapioca starch and other thickeners behave differently. Their required amounts depend on fruit juiciness, acidity and baking time. Mix starch evenly with sugar before adding it to fruit to reduce clumps. Do not assume one thickener can replace another in equal volume.
Vent and bake thoroughly
A top crust needs vents for steam. Bake until the crust is deeply golden and the filling bubbles near the centre, not only at the edge. A tray beneath the pie can catch drips. Protect the edge if it browns before the centre is ready.
Cool before slicing
Hot fruit filling is fluid. Cooling gives the thickener time to set and protects diners from very hot syrup. Serve warm rather than straight from the oven, and refrigerate leftovers when the recipe or filling requires it.