Bittersweet Chocolate Cupcakes

Instructions
Preheat oven to 350 degrees. Line 24-muffin tins with paper liners. In a mixing bowl, blend the cake mix dry ingredients, eggs, oil, water, and sour cream.
Beat at low speed for one minute. Scrape down the sides of the mixer with a spatula. Beat an additional two minutes at medium speed, scraping again if needed so the batter is well blended.
Ladle the batter into the muffin liners, filling each about ⅔ full. Bake 18 to 23 minutes, until a toothpick inserted in the center comes out clean. Remove from the oven.
Cool on a wire rack. For the optional center, gently cut a ¾-inch hole in the center of each cupcake using a narrow spoon or coring tool. Remove the center from each cupcake and reserve.
With a piping bag or squeeze bottle, fill each hole with caramel sundae or dulce de leche sauce and seal the hole with reserved cap of cake cut from the hole.
