Birthday Cakes Dirt Bike Recipe For "grown Up" Dirt Cake?

Recipe for "grown up" dirt cake? - birthday cakes dirt bike

As the daughter of my friend always had birthday cake on their sides, so that this year his 23rd I have a birthday cake of dirt mixed with a certain type of alcohol in the idea of Kahlua or Bailey's, but would be open to other suggestions. Who knows when to add / where / how much? I do not want to guess and destruction. Thank you!