Dough: (Note: All the ingredients should be kept very cold. Try not to use your hands as they will warm the ingredients -use a spoon to mix the ingredients.) Mix the flour and salt. Grate the butter into the mix using the side of the grater with the largest holes. Mix gently - the mixture will be lumpy (The pockets of butter within the dough will help make the crust fluffy). Now add ice cold water 1 Tbsp. at a time until the dough just comes together.
Form the dough into a ball, wrap with plastic wrap, and place in the refrigerator for 20 minutes. (The dough can be made ahead of time and stored in the refrigerator for several days if needed.)
Pie: Preheat the oven to 400 degrees F. Roll out the dough into a circle until the dough is about 1/4" thick. Peel and core the apples and cut into slices 1/4" thick. Place the apple slices onto the dough, slightly overlapping the slices, and leaving an edge of dough about 2" wide all the way around. Sprinkle the apples with sugar, cinnamon (optional), and dot with butter. Fold over the edge of dough onto the slices, pinching the dough at the corners. Sprinkle the edges with a little water and sugar.
Using a spatula place the open face pie onto a baking sheet and bake on the middle rack for 30-35 minutes. When the edges of the crust are golden brown and the filling is bubbly, remove from the oven and let cool.