Pulse flour, sugar, and 1 teaspoon salt in a food processor until combined. Add butter, and pulse until mixture resembles coarse meal, about 10 seconds. Drizzle 1/4 cup ice water evenly over mixture. Pulse until mixture holds together when pressed between 2 fingers (dough should not be wet or sticky). If dough is too dry, add more water, 1 tablespoon at a time, and pulse.
Shape dough into 1 large disk or 2 small disks, and wrap in plastic wrap. Refrigerate until firm, at least 1 hour.
To make the pastry leaves, roll out dough (scraps can be used) to a 1/4-inch thickness on a lightly floured surface, and cut out leaves using floured cookie cutters. Bake on a parchment-lined baking sheet at 350 degrees, rotating sheet halfway through, until pale gold, about 12 minutes.