Moist Vanilla Cupcakes Recipe

Name: Moist Vanilla Cupcakes Recipe
Prep time: 15 min
Cook time: 20 min
Total time: 35 min
Cuisine: American
Ingredients: 1⅔ cup all-purpose flour (213g); 1 cup granulated sugar (200g); ¼ teaspoon baking soda; 1½ teaspoon baking powder; ¼ teaspoon kosher salt; ¾ cup unsalted butter (170g, melted); 3 egg whites (room temperature); 1 tablespoon vanilla extract (15mL); ½ cup sour cream (120mL, room temperature); ½ cup whole milk (120mL, warm); 2 pound confectioners sugar (900g, sifted); 1 pound unsalted butter (450g, room temperature); 1 teaspoon vanilla extract; 1 tablespoon heavy cream; 1 pinch kosher salt; 1 tsp whole milk