Measure your flour into a large bowl.
Cut cold butter into small cubes and add to flour.
Cut butter into flour with a dough/pastry blender until it has a pea-like consistency.
Slowly add the ice water one tablespoon at a time until the flour is well moistened, and the dough leaves the sides of the bowl. The Einkorn flour dough will be a bit stickier than All-purpose flour dough, so have plenty of flour sifted onto your surface, hands, and rolling pin. Turn out the dough and pack it into a ball.
Cut the ball in half and shape each piece into a flattened round disc. Wrap in plastic wrap and chill for a minimum of 45 minutes. Overnight is best.
Roll the first disc of dough out on a floured surface into a circle that is about 3” larger than your pie plate and roughly 1/8" thick.
Gently transfer the bottom crust into the pie plate being careful not to stretch the dough as this will cause it to shrink during baking. (hint: an easy way to do this is to roll it onto your rolling pin loosely and then roll it back out over the pie plate).
Repeat step 6 with the top crust.
Add your pie filling.
Gently transfer the top crust onto the top of the pie.
Trim any extra long edges from the overhanging crust so you have a uniform round shape, then fold and roll overhanging pastry under the edge of the bottom pastry to seal. Lastly, flute the edge with your fingers.
Brush the top of the crust with your egg wash and sprinkle with cinnamon and sugar if desired.
Cut slits in the pie for venting.
Cover the edge of the crust with tin foil while baking to prevent excessive browning. Remove it for the last 15 minutes of baking time.
Bake as directed for your pie recipe.