How to Make It
Preheat oven to 375ºF. Lightly grease muffin pans.
Prepare Batter: Beat butter at medium speed with an electric mixer until creamy; gradually add 1/3 cup sugar, beating until light and fluffy. Add egg, beating well.
3. Combine 2 1/3 cups flour, 1 Tbsp. plus 1 tsp. baking powder, and 1/2 tsp. salt; gradually add to butter mixture alternately with milk, beginning and ending with flour mixture and beating well after each
addition. Stir in vanilla, and fold in blueberries. Spoon batter into prepared muffin pans, filling two-thirds full.
Prepare Streusel Topping: Combine 1/2 cup sugar, 1/3 cup flour, and 1/2 tsp. cinnamon; cut in 1/4 cup
butter with a pastry blender until crumbly. Sprinkle on top of muffin batter.
Bake at 375ºF for 35 minutes or until golden brown. Remove from pans immediately.
Trade the blueberries for raspberries or blackberries for a change.