Blueberry Streusel Muffins
["1/4 c. butter", "1 egg", "1 Tbsp. plus 1 tsp. baking powder", "1 c. milk", "1 1/2 c. fresh or frozen blueberries, thawed", "1/3 c. all-purpose flour", "1/4 c. butter or margarine, softened", "1/3 c. sugar", "2 1/3 c. all-purpose flour", "1/2 tsp. salt", "1 tsp. vanilla extract", "1/2 c. sugar", "1/2 tsp. ground cinnamon"]
["Cream the butter. Gradually add 1/3 cup sugar, beating at medium speed of an electric mixer until light and fluffy.", "Add egg, beating well. Combine 2 1/3 cups flour, baking powder and salt. Add to creamed mixture alternately with milk, stirring well after each addition. Stir in vanilla extract and fold in blueberries. Spoon batter into greased muffin pans, filling 2/3 full. Combine 1/2 cup sugar, 1/3 cup flour and cinnamon. Cut in 1/4 cup butter with a pastry blender until mixture resembles crumbs. Sprinkle on top of muffin batter. Bake at 375\u00b0 for 25 to 30 minutes or until golden brown. Remove from pans immediately."]
["butter", "egg", "baking powder", "milk", "blueberries", "all-purpose", "butter", "sugar", "flour", "salt", "vanilla extract", "sugar", "ground cinnamon"]