01 - Whisk together flour, salt, and sugar in a large bowl until evenly combined.
02 - Cut cold butter into the flour mixture using a pastry cutter or fingertips until the mixture resembles coarse crumbs with some pea-sized butter pieces remaining.
03 - Gradually add ice water, mixing gently with a fork just until the dough begins to come together. Divide dough in half and form into two discs. Wrap tightly and refrigerate for at least 1 hour.
04 - Roll out one disc on a lightly floured surface to fit your 9-inch pie plate. Carefully transfer dough to plate, pressing gently into the bottom and up the sides. Trim edges even with the rim and refrigerate while preparing the braid.
05 - Roll out the second disc to approximately 1/4 inch thickness. Using a sharp knife or pastry wheel, cut twelve long, even strips about 1/2 inch wide.
06 - Group strips into three sets of four. Pinch the tops of each set together securely. Working with one set at a time, label strips left to right as 1-2-3-4. Cross strip 1 over 2, under 3, then over 4. Repeat with the new left-most strip until fully braided. Repeat for remaining two sets.
07 - Carefully transfer braids to the chilled pie edge, pressing gently to adhere. Trim any excess length. Lightly brush water along the crust edge to help seal if needed.
08 - Refrigerate the assembled pie for 15 minutes to firm the crust. Preheat oven to 400°F.
09 - Whisk egg with milk for egg wash. Brush the braided crust generously with the mixture. For blind baking, line the crust with parchment paper and fill with pie weights or dried beans.
10 - Bake for 12-15 minutes or until golden brown. Remove parchment and weights. If additional baking is needed for complete crispness, return to oven for 3-5 more minutes.
11 - Fill the partially baked crust with your desired filling and complete baking according to your chosen pie recipe instructions.