Line two muffin pans with liners and preheat oven to 350. Prepare cupcake batter as directed on the box. Using a cookie scoop, fill each well ⅔ full with batter (I ended up with 22 cupcakes, not 24).
Bake as directed. When a toothpick inserted comes out clean, remove from the oven and allow to cool completely.
Prepare the white buttercream frosting according to package directions. Fold in the grated chocolate. Spoon into a piping bag, snip the very tip off, and set aside.
Prepare the chocolate buttercream frosting according to package directions, but substitute the coffee for the water. Spoon into a piping bag, snip the very tip off, and set aside.
Slide a large tip coupler into the bottom of a third piping bag. Slide both filled piping bags into the third bag, and pull the ends of the filled bags through the coupler. Cut off both ends of the filled bags at that level and apply your tip. Frost the cupcakes in a swirling motion, so you end up with two-toned swirls.
Sprinkle with espresso beans and serve.