Cut the butter into pea-sized pieces and blend into the flour with a pastry blender or your fingers. When mixture is mealy work in the shortening.
Make a well in the center of the ingredients, and add 5 tablespoons water. Work the water into the dry mix adding the extra tablespoon if it’s hard to form a dough.
On a lightly floured surface, smear the dough with the heel of your hand to further distribute the fats in the dough.
Wrap the dough airtight, and refrigerate it for at least 2 hours.