Recipe for Low-Sugar White Peach Jam can be found here.
1) Cut the butter into small pieces, and put it in the freezer for 10 minutes. Measure out the water, and place it in the freezer until ready.
2) Mix the flour, ½ teaspoon sugar and salt in a bowl. Add half the butter. Using quick, light movements, work it in with your fingers until the texture resembles cornmeal. Work in the remaining butter, leaving pea-sized bits. Add the ice water all at once—you want just enough moisture to hold the dough together. Gather the dough into a ball and wrap it in plastic. Flatten it into a disk and refrigerate for half an hour. Heat the oven to 375 degrees.
3) Roll out the dough in a 12” circle and dust it well with flour. Wrap the dough around the rolling pin and transfer it to a baking pan lined with parchment paper. Generously sprinkle the dough with more flour. Starting at the middle of the dough, spread the jam into a thick layer, leaving a 2-inch margin at the edge. Fold the edges back towards the center. Sprinkle the remaining sugar over the crust.
4) Bake for 40 to 45 minutes until the crust is golden and the jam lightly caramelized. Cool on a rack and serve at room temperature with crème fraiche.