Remove one of your doughs from the fridge and allow it to come to room temperature for 5 minutes before rolling. Set aside a small bowl of flour for dusting. Dust your rolling surface with flour, and roll out your dough into roughly a 12-inch circle, then gently transfer to your pie plate. Fill with fruit pie filling, and transfer to the fridge.
Roll out the second dough the same way, then transfer to the top of your pie. Trim any excess, fold the top crust over the bottom and tuck it under, then crimp as desired. Cut slits in the top crust to allow the steam to escape during baking.
Transfer the whole thing to the freezer for 20 minutes.
Meanwhile, preheat the oven to 425F, and set out a large rimmed baking sheet.
When the pie is frozen quite solid, set the pie plate on the baking sheet. Break an egg into a bowl and mix with a splash of water to make an egg wash, then brush that all over the crust. Sprinkle with the Tablespoon of coarse sugar.
Bake for 20 minutes at 425F. Reduce the heat to 350F and bake for another 30-40 minutes, until the filling is bubbling and the crust is golden brown. (Keep an eye on the crust towards the end of the time for over browning. If the crust seems to be getting too dark tent a large piece of foil over it – just put it on loosely.)
Allow to cool for at least 2 hours before eating.