1. Prepare three 8 inch cake pans with parchment paper circles in the bottom and grease the sides. Preheat oven to 300°F (148°C).
2. Add all the dry ingredients to a large bowl and combine.
3. Add the eggs, milk, vegetable oil, Kahlua and vanilla extract to the dry ingredients and mix well.
4. Add the coffee to the cake batter and mix well. Batter will be very thin.
5. Divide the batter evenly between cake pans and bake for 32-35 minutes, or until a toothpick comes out with a few crumbs.
6. Remove cakes from oven and allow to cool for about 5 minutes, then remove to cooling racks to cool completely.
7. To make the frosting, heat the Kahlua until it just begins to boil, then add the espresso. Stir until dissolved.
8. In a large mixer bowl, combine the butter and shortening until smooth.
9. Add about half of the powdered sugar and mix until well combined and smooth.
10. Add about half of the Kahlua mixture and mix until smooth.
11. Add the remaining powdered sugar and mix until well combined and smooth.
12. Add additional Kahlua mixture until the frosting is the right consistency. If needed, refer to my tutorial on how to get the right frosting consistency.
13. To build the cake, cut the domes off the top of each cake so they are flat.
14. Put the first cake layer on a serving plate and top with 1 cup of frosting. Spread into an even layer.
15. Add the second layer of cake, another cup of frosting and then top the cake with the final layer of cake.
16. Frost the outside of the cake. Use my tutorial for frosting a smooth cake, if desired. Use an icing smoother/decorating comb tool like this one to add a pattern on the sides of the cake.
17. Press some sprinkles into the bottom of the sides of the cake.
18. Pipe some swirls around the top edge of the cake (I use Ateco icing tip #844) and add a few additional sprinkles, then serve.
19. Store the cake in an air tight container. Cake is best for 2-3 days.