Prepare an all butter pie crust according to instructions, chill in the refrigerator while you prep the fruit.
Wash and cut the nectarines. Wash the berries. Toss with the tapioca powder and lemon juice. Set aside.
Preheat oven to 350* F.
Roll out the first pie crust and gently place in the bottom of a 9" pie pan. Brush a thin layer of beaten egg white over the dough. Gently pile the fruit into the pan. Dot with little bits of butter.
Roll out the second pie crust, then cut into slices. Decorate the top, weaving over and under, until a lattice covers the top. Brush the top crust with a bit of milk and/or sprinkle a bit of turbinado sugar.
Bake for 45 minutes or until the crust is browned and the fruit is tender. IMPORTANT (and hard): Let the pie sit for at least one hour before cutting.
Recipe by Baby Bird's Farm and Cocina at https://babybirdsfarm.com/nectarine-pie-recipe/