For the crust: In a food processor, pulse flour with sugar and 1/8 teaspoon of salt until blended. Cut the butter into 1/2-inch pieces, add it to the flour and pulse until it's the size of peas. Add the ice water to the flour mixture and pulse until the dough is evenly moistened. Lightly flour your work surface, transfer the dough to it and pat it into a disk. Cover with plastic wrap and refrigerate for about 30 minutes.

In the meantime make the streusels: In a food processor, pulse 1/3 cup flour with 4 tsp brown sugar until blended. Cut the butter into 1/2-inch pieces, add it to the flour and pulse until it's the size of peas. Set aside.

For the filling: Halve the peaches, pit them and slice them 1/2-inch thick. In a bowl, toss them with the frozen berries, the brown sugar, the vanilla extract, a pinch of cinnamon, a pinch of salt, and 2 tbsp all-purpose flour.

On a lightly floured work surface, roll out the dough to a 12-inch (30cm) round. Line a rimmed baking sheet with parchment paper and transfer the rolled out dough to it. Mound the berry-peach mixture in the center of the dough but leave a 2-inch (5cm) border all around. Fold the edge of the dough up and over the berry-peach mixture. Refrigerate the crostata until chilled, about 30 minutes.

Preheat the oven to 425F (218C).

Brush the rim of the crostata with cream and sprinkle with coarse brown sugar. Bake for about 50 minutes until the crust is golden. Let cool for a few minutes before serving.