Place your bottom crust into the pie plate.
Pour your berries into the pie plate.
Add butter on top if desired.
Cover with your crust.
Brush your pie crust with the egg then sprinkle the sugar on top.
Pinch the seams together and mark your pie vents as you like.
Using the lowest rack of your oven, bake for 15 minutes at 425 degrees, then lower the temperature to 350 degrees and bake for about 50-55 minutes more.
When your pie edges start to become too brown - and they always will- cover the edges with tinfoil or use a pie crust cover. I have one and they are amazing!
Continue baking until you see the pie filling bubbling and your pie is beautifully browned all over the top.