I have yet to prove this to myself, but apparently muffins, souffles and the like rise better without papers lining the trays, as they can cling to the butter on the tins and so have a better hold to climb to the top. However, it's the look and convenience of the muffin papers that keeps me going back to them.
Makes 12 Muffins
3 cups flour
3 tsp baking powder
1 tsp salt
6 tbsp butter
1 1/4 cups sugar
2 large eggs
1 tsp pure vanilla extract
1 cup milk
1 3/4 cup fresh or frozen blueberries
Butter or line muffin tins, set aside.
Heat oven to 375 F.
Combine flour, baking powder and salt. Set aside.
In a large bowl, cream butter with sugar with an electric mixer, on medium speed, until fluffy, about 3 minutes. Add eggs and vanilla, mix until well combined. Reduce speed to low, alternate adding flour mixture and milk to mixer, beginning and ending with flour. Gently fold in blueberries with a spoon. (When using frozen berries, leave these in the freezer right until mixing in, or the juices will begin to come out and throw off the muffin batter.)
Divide among muffin tins, sprinkle generously with sugar, if desired.
Bake until light golden, about 30 minutes.
Cool in pan for 15 minutes, then transfer to a cooling rack.