1. Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
2. In a mixing bowl, combine flour, sugar, and salt. Add cold butter and mix until the mixture resembles coarse crumbs.
3. Gradually add ice water, one tablespoon at a time, until the dough comes together. Form into a disk, wrap in plastic, and refrigerate for 30 minutes.
4. On a floured surface, roll out the dough and cut into 4 circles. Transfer to the prepared baking sheet.
5. In a bowl, toss the sliced fruit with lemon juice, cornstarch, and sugar. Divide the fruit mixture among the dough circles, leaving a border around the edges.
6. Fold the edges of the dough over the fruit, pleating as necessary. Sprinkle with additional sugar.
7. Bake for 20-25 minutes, or until the crust is golden and the fruit is bubbly. Let cool slightly before serving.