• Preheat oven to 350℉. Fill a cupcake pan with paper liners. (This recipe makes about 18-20 cupcakes)
• This recipe can be prepared in a large mixing bowl, just as when making brownies from a mix. No mixer needed.
• Combine dry ingredients in large bowl and whisk together until combined. (This is the brownie mix, flour, sugar, cocoa powder, and baking powder.)
• Add the remaining ingredients (eggs, sour cream, fudge packet (if your mix has one), hot coffee (or hot water), and melted butter) and stir until well combined. I find it easiest to use a rubber spatula for this step.
• Fill the cupcake liners with approximately ¼ cup of batter each.
• Bake at 350℉ for 18-20 minutes or until a toothpick inserted in the center comes out clean or with just a few crumbs attached.
• Remove the freshly baked cupcakes from the pans just after removing and cool on a wire rack.

For the Chocolate Buttercream

• Add butter and mix on low to medium speed until smooth. Add vanilla and blend into the butter.
• Add powdered sugar, salt, and cocoa powder.
• Add most of the milk and mix on low speed, increasing to medium as the ingredients become incorporated.
• Continue to mix adding remaining milk as needed. It may take 3-5 minutes to reach the smoothness and consistency you like. It will take longer if using a hand mixer. As you mix, the frosting will become very smooth. You can add additional milk (1 Tablespoon at a time) if the frosting is too thick or additional powdered sugar if too soft.

Decorating the Cupcakes

• Once the cupcakes have completely cooled, frost them however you like! We used a disposable piping bag fitted with a star tip 21, to decorate the cupcakes with piped shells (and mini chocolate chips for some).
• Store in an airtight container, under a cake dome, or in a bakery box for 1-2 days. After that, you can refrigerate for freshness (but allow to warm to room temp before serving).