Buy blueberries in season at peak quality and lowest price. Wash and dry them on paper towels, place in a single layer on a baking sheet and freeze. Place frozen berries in plastic bags and store for up to 9 months.
2 cup all-purpose flour
1/2 cup sugar
1 Tbsp baking powder
1/2 tsp salt
1 1/2 cup fresh or frozen blueberries
1/2 cup sour cream
1 egg slightly beaten
1/2 cup milk
6 Tbsp melted butter or margarine melted
1 tsp grated lemon peel
2 tsp lemon juice
Line a 12-cup muffin pan with paper liners. Combine flour, sugar, baking powder and salt in a medium bowl. Toss berries with 3 tablespoons of flour mixture in a small bowl; coat well.
Preheat oven to 400°F. Whisk sour cream, egg, milk, butter, lemon peel and lemon juice in a large bowl. Add flour mixture to bowl; mix just until moistened. Gently fold in blueberries.
Spoon batter into prepared muffin cups. Bake until a toothpick inserted in center comes out clean or until muffins are golden brown, about 25 minutes. Place pan on a wire rack to cool.
Turn muffins out onto rack. Serve warm or at room temperature.
For mini muffins, use miniature muffin cups that hold just a spoonful of batter. They will bake in only 10 minutes. Prevent warping your muffin pan by adding 2 or 3 tablespoons of water to each empty muffin cup.