This showstopping dessert combines layers of moist cocoa-infused cake with velvety frosting, all crowned with a glossy chocolate cereal topping.
For a less sweet version, reduce sugar to 1 1/4 cups. Substitute sour cream with Greek yogurt if needed. Use Dutch-processed cocoa powder for a deeper chocolate flavor. If you don’t have espresso powder, dissolve 1 tsp of strong coffee grounds in hot water instead.