Preheat oven to 325℉
For crust: combine ¼ cup flour with ice water and lemon juice in a small bowl. Whisk until combined, then set aside.
Next combine ¾ cup flour, powdered sugar and salt in medium bowl, cut shortening in using a pastry cutter or large fork until the mixture resembles course meal.
Add flour mixture from small bowl and mix with fork until blended together. Form into a rough ball.
Lay pastry dough ball onto plastic wrap in center, fold plastic over. Press dough into a flattened circle. Plastic wrap should have extra room on either side.
Roll dough into 12 inch circle.
Place dough in freezer for 10 minutes.
While dough hardens, mix up custard filling. See instructions below.
Remove pie crust from freezer, remove plastic wrap on one side and press unwrapped pastry crust into Cooking Oil Coated pie pan. One you have pressed the crust into the pan, remove the plastic wrap completely and discard. Place back into freezer for 10 more minutes.