Cream butter and sugar together. Add egg and mix well

In seperate bowl, combine dry ingredients. Add to creamed ingredients slowly, alternating with the milk.

Stir in vanilla

Gently fold in blueberries and fill muffin cups 2/3 full.

In a small bowl, combine sugar, flour and cinnamon

Cut in the butter till the mixture resembles coarse crumbs. Sprinkle over muffins.

Bake at 375°F for 20 - 25 minutes, or until a toothpick inserted in the middle of muffin comes out clean. Makes 12 large muffins