Blueberry Muffins
["1/2 c. butter", "1 c. sugar", "2 eggs", "2 c. flour", "2 tsp. baking powder", "1/2 tsp. salt", "1/2 c. milk", "1 tsp. vanilla", "1 1/2 c. frozen blueberries", "2 tsp. sugar (top)"]
["Preheat oven to 375\u00b0."]
["butter", "sugar", "eggs", "flour", "baking powder", "salt", "milk", "vanilla", "frozen blueberries", "sugar"]