Sift dry ingredients together to mix well. cut in the butter until mixture resembles coarse crumbs.
Whisk egg vigorously to incorporate air and make the eggs light. Stir in egg, milk and vanilla and combine thoroughly. Add to dry mixture and stir together (some lumps should remain) and add the blueberries.
Fill well greased muffin tins with batter until two thirds full.
Bake in a pre-heated 350 degree oven for 20 minutes or until done.
Makes 18 large muffins.
Submitted by: CM