One Recipe All Butter Double Pie Crust. Divide the dough in half. Roll out one portion 1/8 inch thick and line the pie pan or tart shell. Refrigerate the shell for 30 minutes. After 30 minutes, dock the shell with a fork, sides and bottom.
Combine the tapioca and cornstarch with just enough of the fruit juice to make a slurry.
Combine the nutmeg, cinnamon, lemon juice, sugar, salt and the remaining fruit juice and bring to a boil. Add the slurry and return the mixture to a boil, stirring constantly. Add the peaches and bring to a boil once again. Add the butter and gently stir it in until melted. Cool completely.
Spoon the filling into the pie shell. Sprinkle the uncooked, fresh blueberries over the cooked peach mixture. Brush the rim of the dough with egg wash.
Roll our the remaining dough 1/8 inch thick and place it over the filling. Or with a pastry wheel, cut the shell into strips for a lattice topping. Brush the lattice top with egg wash. (1 egg, slightly beaten and 1 teaspoon water or cream) Crimp edges to seal.
Bake at 425 degrees just until the crust is lightly browned. About 45 minutes. Allow to cool on a wire rack before serving.