Instructions

Make the Sugar Crumble:

1. In a medium bowl, add the dry ingredients for the crumble: 1 and 1/2 cups flour, 1/3 cup white sugar, 3/4 cup packed brown sugar, and 1/2 teaspoon kosher salt (use less for table salt). Whisk together.
2. In a small bowl, melt 3/4 cup butter (1 and 1/2 sticks). Pour the butter over the dry ingredients and stir together gently. You should end up with a pretty wet sandy mixture with some large clumps. Let it chill in the fridge until you are ready to assemble. 

Rhubarb Filling:

1. Place chopped rhubarb into a medium-sized bowl. Add sugar, cornstarch, salt, and vanilla and stir together.

Assembly and Baking:

1. Preheat oven to 425°F. On a lightly floured surface, roll out one disc of pie dough to a 14-inch diameter. Transfer to a 9-inch round pie plate and trim excess dough away from rim. Spoon in rhubarb mixture. Cut butter into small pieces and nestle them in the rhubarb
2. Top the pie with about a cup or two of the sugar crumble, not all of it! You only want to add enough to cover all the rhubarb, not piling it on. Place the remaining crumble back in the fridge to chill.
3. Bake the pie at 425 for 25 minutes. Then, reduce the heat to 350 degrees without taking it out of the oven.
4. Bake at 350 for an additional 10 minutes.
5. At this point, remove the pie from the oven and shut the oven door.
6. Sprinkle the remaining chilled crumble all over the top of the pie. Break up large pieces with your fingers. Place the foil on top of the pie crust (the center of the pie should be exposed). Loosely crimp it around the crust on the edge. This will protect the edges from burning.
7. With the oven still at 350, place the pie back in the oven and bake for about 30-40 more minutes.
8. You will know the pie is done when the edges of the crust are brown and the crumble is turning a light golden brown in the center. If you want your crust and crumble to brown a little more, remove the foil shield and bake another 5-10 minutes.
9. Let the pie cool on a wire rack for about 4 hours.