Preheat oven to 350°F (180°C). Liberally grease two 8″ round cake pans with vegetable shortening, and/or spray with baking spray.
Combine flour, sugar, baking powder, salt, and pudding mix in a large mixing bowl. Add in eggs, beating just until smooth. Carefully add melted butter to the batter, mixing on medium speed until smooth.
Divide batter evenly into two bowls. Add water and blood orange essential oil to one bowl, beating until well incorporated and smooth. Taste, adding more blood orange essential oil if desired. Tint orange, if desired.
Add cocoa powder to second bowl, stirring until evenly distributed. Add coffee, beat once more until fully incorporated and smooth.
Divide batter among prepared cake pans, one flavor per pan.
Bake until golden and knife inserted into center of batter comes out clean and cake springs back – about 45-60 minutes.
Allow to cool 10-15 minutes before turning cakes out onto baking rack to cool fully. Ideally, allow to cool to room temperature, wrap tightly with plastic wrap.
Allow cake to sit overnight.
Prepare a batch of milk chocolate whipped ganache, flavoring the whipped cream – while heating – with blood orange extract
Prepare Swiss meringue buttercream, flavoring it with Bailey’s instead of the vanilla.
To Assemble Cake
Remove plastic wrap from cake layers. Carefully slice the domed top off each round, leveling the surface of the cake. Carefully cut each cake in half, horizontally, for 4 thin rounds of cake in all.
Place one round of orange cake on cake plate, spread with ganache. Top with a round of mocha cake, spread with buttercream. Top with second round of orange cake. Spread with a final layer of ganache, and top with remaining layer of mocha cake. Frost sides and top of cake with remaining buttercream. Serve at room temperature.
Note: This cake gets VERY hard when chilled. Always serve cakes at room temperature! Cold cake is DRY cake.