Step 1 Place the butter, egg, sugar, milk and salt in the bowl of a food processor. Pulse on/off until the butter is coarsely chopped. Spoon the flour evenly over the butter. Process just until the dough is crumbly and beginning to cohere but not in a ball (overprocessing will toughen the dough). Transfer the dough to a work surface. Gather the dough together and knead it, folding it back on itself, until it's in a smooth ball. Flatten it into a disk. Wrap the dough in plastic; refrigerate at least 2 hours or up to 2 days. (It can also be frozen up to 1 month; thaw in the refrigerator.)
Step 2 Let the chilled dough rest at room temperature for 10 minutes before rolling. Roll the dough on a well-floured surface into a circle about 1/4 inch thick. Do not roll it too thin; it tastes better thicker. Transfer it to a 9-inch quiche or springform pan (1 to 1 1/2 inches deep) with a removable bottom. Press it into place without stretching the dough. Trim the pastry edge for a 1-inch overhang. (Reserve any pastry scraps for patching later.) Fold the overhang inside to form double-thick sides. Press this dough firmly into place, pushing the crust up 1/4 inch above the edge of the pan to allow for any shrinkage during baking. Refrigerate until the dough is firm, about 1 hour (or freeze briefly). Line the shell with parchment paper or foil; fill with dried beans.
Step 3Heat the oven to 375 degrees.
Step 4Bake until the dough is starting to set, about 16 to 18 minutes. Carefully lift out the paper and beans; continue to bake until lightly browned, about 15 minutes more. Patch any cracks with thin scraps of the reserved dough; it is not necessary to bake patches. The shell can be filled while still hot from the oven.