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 dry ingredients to a large bowl and whisk together.
3. Add eggs, buttermilk and vegetable oil to the dry ingredients and mix well.

4. Add vanilla to boiling water and add to mixture. Mix well.
5. Divide batter evenly between cakes pans and bake for 30-33 minutes, or until a toothpick comes out with a few crumbs.
6. Remove cakes from oven and allow to cool

7. Make frosting while cakes cool. Beat together butter and shortening until smooth.
8. Slowly add 4 cups (460g) of powdered sugar and mix until smooth.
9. Add vanilla and half of the water or milk and mix until smooth.
10. Add another 5 cups (575g) of powdered sugar and mix until smooth.
11. Add cocoa and mix until smooth.
12. Add remaining water or milk until the frosting is the right consistency

13. Once cakes are cool, remove cake domes from top with a large serrated knife. See my tips on how to level a cake and how to stack a cake.
14. Place first layer of cake on cake plate. Spread about 1 cup of frosting on top in an even layer.
15. Add second layer of cake and add another cup of frosting on top in an even layer.
16. Add final layer of cake on top and frost the outside of the cake. Feel free to use my tutorial for frosting a smooth cake

17. To make the chocolate ganache, add the chocolate chips to a medium sized bowl (see my tips on making chocolate ganache).
18. Heat the heavy whipping cream just until it begins to boil, then pour it over the chocolate chips. Allow it to sit for 2-3 minutes, then whisk until smooth.
19. Drizzle the chocolate ganache around the edge of the cake, then pour the remainder of the ganache on top of the cake and spread evenly. I like to use a squeeze bottle for drizzling around the edges.

20. Allow the ganache to firm up a bit, then pipe the remainder of the frosting around the top edge of the cake and pipe a border around the bottom. I used Ateco tip 844.
21. Add a few sprinkles to the cake, if desired, then serve. Cake is best when well covered for 3-4 days.