St. Patrick's Day Cupcakes

Name: St. Patrick's Day Cupcakes
Prep time: 30 min
Cook time: 16 min
Total time: 46 min
Cuisine: American
Ingredients: 2 cups + 2 tablespoons all-purpose flour; 4 1/2 tablespoons corn starch; 2 tablespoons unsweetened cocoa powder; 1 teaspoon baking powder; 1/2 teaspoon baking soda; 1/4 teaspoon salt; 3/4 cup butter (room temperature); 1 1/2 cups sugar; 3 eggs (room temperature); 1 1/4 cup sour cream; 1 tablespoon vanilla; 1 1/2 tablespoons green liquid food coloring; 12 ounces cream cheese; 6 tablespoons butter; 4 cups powdered sugar; 2-3 tablespoons heavy whipping cream (or milk); 1/2 teaspoon vanilla; Sprinkles; Chocolate gold coins