This blueberry peach galette recipe pairs ripe, sliced peaches with whole blueberries inside a single sheet of buttery pastry, folded loosely around the fruit instead of sealed into a pan.
Whisk flour, 1 tablespoon sugar, and ¼ teaspoon salt. Cut in cold butter until coarse crumbs form. Add ice water 1 tablespoon at a time until dough holds together. Shape into a disc, wrap, and chill for 30 minutes.
In a bowl, combine sliced peaches and blueberries. Add ⅓ cup sugar, cornstarch, lemon juice, cinnamon, vanilla, and a pinch of salt. Toss gently to coat.
Preheat oven to 400°F (200°C) and line a baking sheet with parchment. On a floured surface, roll chilled dough into a 12-inch (30 cm) circle. Transfer to the prepared baking sheet.
Spoon fruit filling into the center, leaving a 2-inch (5 cm) border. Fold the dough border up and over the fruit, overlapping every 2-3 inches (5-7.5 cm).
Whisk egg with 1 tablespoon water. Brush egg wash over the crust and sprinkle with turbinado sugar. Bake for 35-40 minutes until golden and bubbling.
Cool on the baking sheet for 10 minutes before transferring to a wire rack. Slice and serve warm or at room temperature.
Notes
Butter Temperature: Keep the butter cold right up until it goes into the flour. If it starts to soften while you're cubing it, put it back in the fridge for a few minutes first.
Choosing Peaches: Use peaches that give slightly when pressed but aren't soft or bruised. Underripe peaches won't release enough juice, and overripe ones can make the filling too watery.
Drain Excess Liquid: Don't skip draining the excess liquid from the fruit bowl before filling the dough. Extra liquid on top of the cornstarch can overwhelm the crust.
Folding the Crust: Fold the crust edges snugly against the fruit rather than loosely. A loose fold is more likely to let juices leak out during baking.
Chill Before Baking: Chill the assembled, unbaked galette on the sheet pan for 10 to 15 minutes before baking. This helps the folded edges hold their shape instead of slumping in the oven.
Prevent Over-Browning: If the crust is browning faster than the center is setting, loosely tent the galette with foil for the last 10 minutes of baking.
Frozen Fruit: Frozen fruit works, but it releases more liquid. Thaw and drain well first, and consider adding an extra teaspoon of cornstarch to compensate.
Make Ahead: The dough can be made up to 2 days in advance and kept wrapped in the refrigerator. It can also be frozen for up to 1 month.
Storage: Store at room temperature for 1 day, or refrigerate in an airtight container for up to 4 days. The crust will soften over time.
Reheating: Warm slices in a 350°F (175°C) oven for 8-10 minutes to re-crisp the crust. A microwave will heat it through but leaves the crust soft.