1/2 c. butter, at room temperature
1 c. sugar
2 lg. eggs
1 tsp. vanilla
2 tsp. baking powder
1/4 tsp. salt
2 1/2 c. fresh blueberries or 12 oz. bag frozen blueberries, not thawed
2 c. all purpose flour
1/2 c. milk

Heat oven to 375 degrees. Grease 18 or 20 muffin cups or line with paper baking cups. Beat butter with mixer until creamy. Add sugar and beat until pale and fluffy. Add eggs, one at a time, beating after each addition. Beat in vanilla, baking powder and salt. If using fresh berries mash 1/2 cup and stir into batter. With rubber spatula, fold half the flour, then half the milk into batter. Repeat with remaining flour and milk. Fold in remaining fresh blueberries or all the frozen. Spoon batter into muffin cups. Bake 25 to 30 minutes until golden brown and top feels springy when touched. Makes 18 large or 20 regular size muffins.