4th of July Red, White & Blue Cupcakes - One Dish At A Time

Ingredients

• 1½ cups all-purpose gluten-free flour
• 1 cup granulated sugar
• 1½ teaspoons baking powder
• ½ teaspoon table salt
• 8 tablespoons unsalted butter (1 stick), room temperature
• ½ cup sour cream
• 1 large egg , room temperature
• 2 large egg yolks , room temperature
• 1½ teaspoons vanilla extract
• 6 tablespoons blue food coloring (liquid)
• 1 1/2 sticks unsalted butter, softened
• 1 pound (3 2/3 cups) confectioners' sugar
• 1 to 2 tablespoons milk (optional)