Use these shells to make Salmon-Mousse Tartlets.
In a food processor, pulse all the ingredients until the butter pieces are about the size of peas. Add as much as 1/2 cup cold water a little at a time through the feed tube, pulsing until the dough just comes together. Do not overmix.
Divide the dough in half, then press the halves to flatten them into disks. Wrap each disk in plastic. Place the disks in the refrigerator at least 30 minutes.
Preheat the oven to 375 degrees. Roll each disk of dough to 1/8 inch thick; use a biscuit cutter to cut out 3-inch rounds. Gently fit the rounds into 2 1/2-inch tartlet pans (chill unused rounds until ready to bake). Cover with aluminum foil; fill with dried beans or pie weights.
Bake 15 minutes. Remove foil and weights; continue baking until golden, 10 to 15 minutes. Let cool completely.