1
In a large bowl, mix flour, sugar, salt and pie spice; cut in shortening and butter until crumbly. Gradually add ice water, tossing with a fork until dough holds together when pressed. Shape into a disk; wrap and refrigerate 1 hour or overnight.
2
Preheat oven to 400°. On a lightly floured surface, roll dough to a 1/8-in.-thick circle; transfer to a 9-in. pie plate. Trim crust to 1/2 in. beyond rim of plate; flute edge. Refrigerate while preparing filling.
3
For the topping, in a medium bowl, whisk together flour, sugars, crushed cookies and salt. Stir in oats and pecans. Add the butter and vanilla until small clumps form. Set aside.
4
In a large bowl, toss peaches and cherries with lemon juice and vanilla. In a separate bowl, whisk together sugars, potato starch and salt. Add to fruit, toss until well coated.
5
Transfer filling to prepared crust. Sprinkle with reserved topping; pressing down to adhere as needed. Bake for 20 minutes. Reduce oven setting to 350°, bake until crust and topping are golden brown and fruit is bubbly, 20-25 minutes longer. Cool completely on a wire rack.
