First make your crust! In a food processor mix together the flour and salt. Pulse the the cold butter, a few cubes at a time until it is a crumbly mixture.
Add 1 tablespoon of ice water at a time to the dough until the mixture comes together.
Typically it takes 3 tablespoons of ice water to get it to come together.
Divide and press into 2 equal disks. Wrap in plastic wrap in place in the refrigerator for at least 1 hour.
After and hour, roll out 1 of the disks to about 11 inches in diameter and 1/2 inch thick.
Place the rolled out dough into a 9 inch pie pan. Cover the pan with foil and fill with a pie weights or something like dry rice or dry beans.
Bake at 425º for 25 minutes and golden.
While that bakes, make the filling!
Drain half of the juice from the cherries. Pour the juice and cherries into a large bowl.
Add 3/4 cup sugar, cognac, corn starch, nutmeg and salt. It you like a more juicy pie add less cornstarch. If you want it to be more firm, add 2 tablespoons of cornstarch.
Give it a good stir and then pour into the baked pie shell.
Roll out the other disk and place on top of cherry filling.
Whisk the egg and brush it the egg wash on top of the dough before baking.
Bake at 375º for another 55 minutes or until golden brown and bubbly.
Remove from the oven and allow it to cool for at least 2 hours before cutting. Enjoy!