Preheat oven to 350 degrees F. Lightly grease a 9x9 baking pan.
In a large mixing bowl, toss the berries with lemon juice, sugar, cornstarch, 1/2 teaspoon cinnamon, and vanilla. Scoop into prepared baking pan with all the juices.
In a medium-sized bowl or food processor, combine flour, sugar, and 1/2 teaspoon cinnamon. Use a pastry cutter or food processor to cut in cold butter, you want it all combined but a variety of sizes in clumps.
Sprinkle mixture over the top of the mixed berries in an even layer.
Bake in the preheated 350 degree oven, uncovered, for 40-45 minutes until crumble is toasted and lightly browned.