2 c. flour, sifted
1 c. granulated sugar
1/2 c. butter
2 tsp. baking powder
1/2 tsp. baking soda
2 eggs
1/3 c. milk
1 tbsp. white vinegar
1 c. blueberries, fresh or frozen, thawed & drained

Mix flour and sugar together and cut in butter (as for pie crust). Reserve 1/2 cup crumbs for topping. To remaining flour and sugar mixture add baking powder and soda. Separate eggs and mix yolks with milk and vinegar. Mix only until flour mixture is moistened. Beat egg whites until stiff and fold in. Fold in blueberries. Fill muffin cups 2/3 full, top with reserved crumbs. Bake at 375 degrees for 12 to 15 minutes. Makes 16 to 18 muffins.