How to Make It
In a food processor, pulse the flour with the sugar and salt. Add the butter and pulse until the mixture resembles coarse meal. Drizzle the water over the mixture and pulse just until a dough forms. Turn the dough out onto a lightly floured surface and pat it into a disk. Wrap in plastic and refrigerate for at least 30 minutes.
Preheat the oven to 425°. Cut the dough into 8 equal pieces. Working with 1 piece at a time and keeping the rest refrigerated, roll the dough between 2 sheets of wax paper into a 4-inch round. Refrigerate the pastry round and repeat with the remaining dough.
Arrange the pastry rounds on a baking sheet and bake about 15 minutes, or until golden brown. Transfer to a rack and let cool.
Butter a large rimmed baking sheet. Spread the peaches on the sheet and sprinkle with the granulated sugar. Roast for 15 minutes, or until the peaches are soft and slightly browned at the edges; let cool.
In a medium bowl, beat the heavy cream with the 1 tablespoon of confectioners' sugar until soft peaks form. Place 4 of the pastry rounds on plates. Top them with half of the peaches and half of the whipped cream. Lay a second pastry round on the cream and top with the remaining peaches and whipped cream. Sprinkle with confectioners' sugar and serve immediately.