Mix-In Muffins - cooking recipe

Ingredients

1 1/2 c all-purpose flour
1/3 c sugar
1 1/2 tsp baking powder
1/4 tsp baking soda
1/4 tsp salt
1 stick butter, unsalted
1 c sour cream
1 large egg
1 tsp vanilla

Preparation

Preheat oven to 400 degrees and line a 12 (1/3-cup) muffin cups with paper liners.