Roll the prepared pie dough out into a 13-inch circle. Roll the dough carefully over the rolling pin and transfer it to a 9-inch the pie plate. Tuck the dough into the bottom and sides of the plate. Snip the dough hanging over the edge leaving a 1-inch overhang. Fold this dough under itself and crimp the edges to seal, in a decorative pattern if desired. Chill the pie shell in the refrigerator for 30 minutes.

In a small mixing bowl, whisk the flour, almonds, brown sugar, and ¼ teaspoon salt. With your hands or a pastry blender, work in the butter until the dry ingredients are incorporated into the butter and large clumps form. Cover and place in the refrigerator.

Place an oven rack in the middle of the oven, place a large sheet of foil on the bottom of the oven, and preheat the oven to 375°F.

In a large mixing bowl, combine the rhubarb, sugar, cornstarch and remaining ¼ teaspoon salt. Toss well to evenly coat the rhubarb with the dry ingredients. Transfer this mixture to the chilled pie shell.

Scatter the crumble mixture evenly over the top of the pie.

Place the pie in the oven. Bake until the topping is bubbling and the crust is browned, about one hour. If the crust browns too quickly, cover loosely with foil. Cool completely before serving.

Serve with whipped cream or a dollop of crème fraîche.