I just love pie, but sometimes you need to feed a crowd and this is just the right size. Use your favorite pie crust recipe or use store bought frozen. Fresh is ALWAYS best, you can use any in season fruit for this pie. YUM!
Roll out enough pastry dough big enough to fit a 12x16 inch pan. Spray pan with cooking spray (you can also line pan with parchment paper). Transfer dough to prepared pan, trim edges of dough leaving 1/2 inch hang over on edge.
For filling: combine sugar, cornstarch and slat. Add sliced peaches and lemon juice and stir. Pour peach filling into prepared baking sheet. Roll out remaining dough. Place on top of filling. Trim edges of dough to hang over sides slightly. Fold edges under and pinch to seal.
Beat egg whites until frothy and brush over top crust. Sprinkle turbinado sugar over top.
Bake at 375 degrees for about 45-50 minutes (depending on your oven) or until golden and filling is bubbling. Allow to cool completely on wire rack several hours. Cut into 20 pieces. Freezes wonderfully.