In a medium bowl, stir together the flour, sugar and salt. Cube the cold butter and use a pastry cutter to cut the butter into the dry ingredients. You can also use your clean fingers to work the butter into pea-sized pieces into the flour.
Make the ice water in a bowl and the add ice water a teaspoon at a time to the dough base until the dough just comes together. You'll probably need about 8 to 10 tablespoons of ice water for this much pie crust. Try not to add too much water.
When you can pull the dough together into a ball, knead it a few times and then divide it into a 2/3 piece and 1/3 piece. The 2/3 piece will be the base of the pie and the 1/3 piece will be the lid. Wrap the pieces separately in plastic wrap and chill in the fridge for at least 30 minutes.
PREPARE THE FILLING:
Preheat the oven to 375 degrees F.
Pit the cherries using a cherry pitter or a chopstick to push the pit out of the fruit. Add the pitted whole cherries to a bowl with the sugar, lemon juice, cornstarch, and a pinch of salt. Let sit for 15 minutes.
Preheat the oven to 375 degrees F. Remove the pie crust from the fridge and roll out the larger piece of pie crust to fit your pan. I use a 10x15inch jelly roll pan, and it fits perfectly. You can roll the pie crust thinner if you have a slightly larger sheet pan, but if you do that then you might need to up the filling on the pie to 7 or 8 cups of fruit.
Press the pie crust into your pan and pour fruit filling into the crust. There should be gaps in the fruit. It shouldn't cover the entire crust as the fruit will expand as it bakes.
Roll out the smaller piece of crust and cut out some circles to show off the cherries. Place the pie crust over the filling, and crimp the edges to attach it to the bottom crust.
Brush the pie with egg wash, and dust liberally with coarse sugar.
Bake the pie for 55 to 60 minutes, rotating once halfway through. Then allow to cool for 15 minutes before slicing and serving.Store leftover pie in the fridge for a few days.