Century-Old Nuns Pastry Dough - cooking recipe

Ingredients

4 cups all-purpose flour
1 tablespoon kosher salt
1/2 lemon, juice of
1/2 lemon, zest of
1 lb lard (recommended ( Tenderflake)
1 egg, separated

Preparation

Whisk the flour, salt and lemon rind in a bowl.
Cut in the lard with a pastry blender or your fingers until the mix resembles a light, floury crumble.
Mix the lemon juice and egg yolk in a measuring cup and top with enough ice-cold water to the 1-cup line.
Whisk the egg white until foamy.
Make a well in the flour mixture.
Add the egg yolk mixture to the flour mixture and gently fold 7-12 times by hand.
While the mix is still a bit floury, add in the whipped egg white and gently press, fold, and press again until all the flour combines into a paste-like ball.
If you're making butter tarts, divide the dough into 2 balls, wrap with plastic wrap, and chill for at least 1 hour before using.
If you're making 10\" crusts, divide it into 3 before wrapping and chilling.