Sour Cream Blueberry Muffins

Details

Ingredients

• cooking spray
• ½ cup all-purpose flour
• ¼ cup brown sugar
• ½ teaspoon ground cinnamon
• ¼ teaspoon salt
• ¼ cup butter, softened
• 2 cups all-purpose flour
• 3 teaspoons baking powder
• 1 teaspoon cinnamon
• ¼ teaspoon salt
• 2 large eggs
• ½ cup granulated sugar
• ½ cup brown sugar
• 1 cup sour cream
• ½ cup vegetable oil
• 1 teaspoon vanilla extract
• 2 cups blueberries
• 1 tablespoon all-purpose flour