Stir together first three ingredients. In another bowl, beat the next two ingredients with a mixer until combined. Add egg and beat till fluffy.

Alternately add the flour mix and milk to the egg mix, beating on low after each addition until just combined. Batter will be a little thick. Gently fold in blueberries.

Spread into a greased 9x9 pan.

For the topping, mix the sugar, flour, and cinnamon. Cut in the butter until the mixture resembles coarse crumbs. Sprinkle over batter, and sprinkle 2 t sugar over that.

Bake at 350 degrees for 40-45 minutes until toothpick comes out clean from the middle. Serve with whipped cream.