Make vanilla cake as per box directions, separate the batter and bake in two 8 inch baking pans. If you don't have 2 baking pans, you can bake in one pan, then cut the cake through the middle to create two cakes.

Drain ricotta and place in a bowl. Combine all ingredients and mix well. Set aside.

Heat one cup of milk until just at boiling.

Place sugar and flour in a double boiler. If you don't have a double boiler, just use a glass or aluminum bowl and place on top of a small pot of boiling water. Be careful not to let the bottom of the bowl touch the boiling water.

Add hot milk and stir continually until thickened.

Lightly beat the egg in a small bowl. Add about half of the flour/milk mixture to the egg a little at a time mixing after each addition.

Return the egg mixture to the double boiler with the remaining milk/flour mixture and continue to mix on the double boiler.

Cook for one minute then remove from heat and let cool. If you don't use the custard immediately, let cool, then place plastic wrap directly on top of the custard and store in the fridge. This will prevent a thin linin of skin buildup on top of the custard.

Reserve half a cup of the Ricotta filling if you will be decorating your cake with cannoli filled with ricotta.

Mix ricotta filling and custard filling together. If you don't want to use all of the custard, don't. Combine them to your preference.

Make the buttercream icing by softened the butter in a stand mixer. Add powdered sugar a little at a time. Use the cream a tablespoon at a time to smooth out the icing. It's not meant to use all the cream, if you need it use it, otherwise only add what you need to get the consistency you need.

Place a dollop of frosting on a cake board and place one layer of the cake on it centered.

Pipe frosting around the edge of the first layer, then place the ricotta filling in the middle.

Top with second layer.

Frost your cake. Don't worry if you make a mess, you are only going to eat it!

Take 4 cannoli shells and pipe the ricotta filling you reserved into the shells. Place a dollop of frosting strategically on four corners of your cake, then top with the ricotta filed cannoli.

Decorate remaining cake with extra chocolate chips. Chill in the fridge.