Mrs. Berry's Berry Coffee Cake

Preheat oven to 400 degrees F (200 degrees C). Grease a 9x11-inch baking pan.

Mix 2 cups baking mix, boysenberries, milk, egg, 2 tablespoons brown sugar, and vanilla extract in a bowl until batter is moist, about 30 seconds. Pour batter into baking pan.

Combine 1/3 cup baking mix, 1/3 cup brown sugar, and ground cinnamon in a bowl; cut in 2 tablespoons butter with a fork, until mixture resembles coarse crumbles. Sprinkle crumbles over the batter until covered.

Bake in the preheated oven until a toothpick comes out clean, 20 to 25 minutes.