Easy Three-Berry Crumble Slab Pie

Prep time: 15 min
Cook time: 45 min
Servings: 18
Yield: 18 servings

Description

This informal 3-berry slab pie with a crumble topping serves a crowd and is baked on a sheet pan! Use frozen berries for a fresh-tasting dessert any time of year.

Ingredients

2 tablespoons all-purpose flour
2 9-inch pie crusts
7 cups frozen mixed berries (blackberries, blueberries, and raspberries)
3/4 cup granulated sugar
1/3 cup arrowroot powder
1/2 teaspoon salt
1 cup rolled oats
1 cup all-purpose flour
3/4 cup packed light brown sugar
1 teaspoon apple pie spice
1/2 teaspoon salt
7 tablespoons cold unsalted butter

Directions

1 Preheat the oven to 375 degrees F (190 degrees C).
2 Lightly dust an 11x15-inch half-sheet pan with flour. Carefully place the 2 pie crusts into the bottom of the sheet pan, gently stretching and trimming the crusts to fit the bottom and up the sides of the pan.
3 Combine berries, sugar, arrowroot powder, and salt in a large bowl; stir well.
4 Combine oats, flour, brown sugar, apple pie spice, and salt in a medium bowl. Use a pastry knife to cut butter into the oat mixture until butter is evenly distributed throughout and the crumble topping mixture resembles small, uneven pieces.
5 Pour berry mixture evenly onto the crust and add crumble mixture on top.
6 Bake in the preheated oven until brown and bubbly, 45 to 55 minutes. Remove and allow to cool for 30 to 45 minutes