01 - Whisk together flour, salt, and sugar in a large bowl until thoroughly combined.
02 - Cut cold butter into flour mixture using a pastry cutter or fingertips until texture resembles coarse crumbs with some pea-sized butter pieces remaining.
03 - Gradually add ice water, mixing gently until dough just comes together. Divide into two equal portions, form into flat discs, wrap in plastic, and refrigerate for at least 1 hour.
04 - Roll one dough disc on lightly floured surface to fit 9-inch pie plate. Press dough gently into plate, trim excess edges, and refrigerate while preparing braids.
05 - Roll remaining dough disc to 1/4-inch thickness. Cut twelve long, even strips approximately 1/2-inch wide using a sharp knife or pastry wheel.
06 - Group strips into three sets of four. Pinch tops together. For each set, working left to right: cross outermost strip over adjacent strip, under next strip, over final strip. Repeat until braid is complete.
07 - Carefully transfer braids to chilled pie edge, pressing gently to adhere. Trim excess dough. Moisten edge with water if needed to seal braids securely.
08 - Refrigerate assembled pie crust for 15 minutes to firm. Preheat oven to 400°F.
09 - Beat egg with milk. Brush entire braid evenly with egg wash using a pastry brush.
10 - Line crust with parchment paper, fill with pie weights. Bake for 12-15 minutes until golden brown. Remove weights and parchment, continue baking if needed for crispness.
11 - Proceed with filling and baking according to your chosen pie recipe instructions.