Continue to mix with a pastry blender while gradually adding the cold water one tablespoon at a time. (You should stop mixing when you see it hold together upon grabbing and pinching some crumbs. If it's still dry, you may add a teaspoon of cold water.) Form into a disk, wrap with a cling wrap, and put on the refrigerator for a minimum of three hours or overnight.
Note: If you don't have a pastry blender, you may use food processor or fork to make the crust and crumbs. You may opt to blind or pre-bake your crust before scooping in your filling. This will prevent the bottom of your pie from being soggy. To blind bake, simply line the bottom and sides of your dough with parchment paper and fill it with uncooked rice or beans then bake for 15 minutes. Once done, remove the uncooked rice or beans and parchment paper, scoop in the filling then bake per instructions.