Preheat the oven to 180 degrees. Grease and flour two 8 inch pans - for the chocolate cake pan, use cocoa powder to flour.

For both the cakes, the procedure is the same. Beat butter and sugar till fluffy and creamy.

Add one egg at a time and beat well after each addition.

Add the vanilla and beat.

In a bowl, whisk together the dry ingredients (flour to salt) till well combined.

Add 1/3 of the flour mixture and beat on low till moist.

Add half the milk and 1/3 of the flour mixture and beat again till just combined

Now add the remaining milk and flour mixture and beat till the mixture is all moist. Keep the beater on low and stop as soon as the cake batter is done. Do not over-beat.

Pour into the prepared pans and bake for 30 minutes or till skewer comes out clean when tested from the center.

Take out the pans, cool cake in the pans for around 10 minutes. You will see the edges moving into the pan.

Flip onto a cooling rack, and cool completely. Cover with cling film and store in the fridge till frosting is to be done.

For the ermine frosting, whisk flour, sugar and milk together in a bowl and cook on low flame till it thickens and becomes a roux. Allow it to cool completely.

The butter must be just soft, not too soft as for usual buttercream, hard to touch but when pressed can leave impressions. Cube them and put into a stand mixer and start beating till creamy.

Add the roux one tablespoon at a time and keep beating till incorporated. Finally scrape in the vanilla bean and fold in.

Bring the cakes to room temperature at the time of frosting. Cut them into half and set aside.

Using two bowls - one small and one medium sized, cut rounds from each of the halves.

Slather a thin layer of frosting in the inside. Overlap and keep to make four portions of vanilla and chocolate layers (like you see in the picture above). The frosting will allow it to stick to each other.

At the end of this exercise, you will have two portions with the CVCV format and with VCVC format. (C = Chocolate, V = Vanilla)

Now keep one CVCV formatted cake ring at the bottom. Slather some frosting to give it a good layer. Put a VCVC formatted cake on the top of it. Slather frosting, put the remaining CVCV, slather some more frosting and finally top with the left over VCVC cake. Be sure to handle it slowly without the inner rings coming out.

Crumb coat the cake (apply a thin coating) all over and allow it to rest in the fridge for an hour.

Take out the cake, and coat with the remaining frosting. Smoothen it out. Allow it to rest for an hour again in the fridge.

For ganache, heat the cream till scalding hot. Do not boil. Pour over the chocolate chips and whisk till all melted and smooth.

Allow it to cool till room temperature. Take out the cake, pour from the middle and using an icing spatula, spread it out on the top and allow it to drip to the sides.

Keep the cake for another 30 minutes in the fridge for the ganache to settle. Top with some M&Ms and enjoy!