I stumbled upon this recipe in Bon Appetit many years ago and it continues to be my favorite fruit pie. You can make it all winter long since all of the fruit is frozen, except for those two apples. I LOVE this pie.
2 unbaked pie crusts
2 large Baking apples, peeled, cored, chopped
1 cup Frozen, chopped rhubarb
1 cup Frozen raspberries, thawed
1 cup Frozen blackberries, thawed
1 cup Frozen strawberries, thawed
1 cup Sugar
1/3 cup All purpose flour
1 tablespoon Fresh lemon juice
Combine all ingredients in large bowl and stir to combine. Spoon mixture into pie crust. Roll out remaining dough disk on lightly floured surface to 11-inch-diameter round. Place round atop pie filling. Trim crust, leaving 1/2-inch overhang. Fold top crust edge under bottom crust edge, pressing to seal. Crimp edges. Cut slits in top crust to allow steam to escape. Place pie on baking sheet and bake 25 minutes. Reduce oven temperature to 350'F and bake until crust is golden and juices bubble, about 30 minutes. Transfer pie to rack and cool.