For the cake : Preheat oven to 180degrees Beat together the eggs , sugar and oil until fluffy , add vanilla Add the flour and baking powder . Mix together the cocoa and water and lastly add this in slowly. Let everything mix . Pour batter in a greased round baking tin and bake for 20 minutes or until done .
Fluff : Beat together egg whites , sugar and cream of tartar until the sugar dissolves and you can see the texture becoming fluffy In the meantime boil the water , remove from heat add the gelatine and continue stirring until all as dissolved . Pour this mix to the fluff and beat for 3 minutes or until glossy . Set aside . Icing : Beat together butter and sugar until white . Add the cocoa and milk and continue beating until well combined . Lastly add the Nutella and beat for another minute , Set aside .
Assemble : Cool the cake completely . Cut the cake in the middle . Add some fluff to the cake as well icing . Sandwich the cake . Add theremaining fluff to the top half and top with the icing . Using a spoon spread and gently mix the topping to create the designs showing some of the fluff .
P.S these can also be made in cupcake form . All you have to do is when the cupcakes are cooled , cut the middle remove a piece , stuff with mellow fluff . Place the cut piece close add the icing and spread . Then you will have stuffed mellow fluff cupcakes 😛