- Preheat oven to 350 degrees.
- Spray a 9 x 13 pan with non-stick cooking spray and set aside.
- In a bowl, add the baking mix and sugar. Stir to combine.
- Next add in the sour cream, eggs, milk and vanilla. Stir together just until combined. Batter will be very thick.
- The gently fold the blueberries into the batter.
- Add the batter to the prepared 9 x 13 inch pan and spread out evenly.
- In another bowl, add the streusel ingredients and cut with a pastry blender until it becomes coarse crumbs. Sprinkle over the batter.
- Bake at 350 degrees for 25-30 minutes or until a toothpick inserted in the center comes out clean. Serves 12-16.