In a bowl, add eggs and sugar. Beat on high speed until it turns light and fluffy.
Pour in milk, oil and vanilla. Mix
Add flour and baking powder. Gently fold until everything gets combined.
Transfer 1/4th of the batter into another bowl and add cocoa powder and 1 tbsp milk into it. Mix.
Grease sandwich maker tray with butter. Pour a tbsp of white batter onto the plate. Then add half a tsp of cocoa batter on top, followed by half tsp of white batter until you add 6 layers.
Close the sandwich maker and cook for 5-6 minutes.
Delicious cakes are ready.