*you can also use regular or decaf coffee. Or replace with ⅓ cup brewed coffee.
Pre-heat oven to 350 degrees (180 degrees celsius)
Grease two 8 or 9 inch (20 or 23 centimeters) round pans.
In a medium bowl beat together for approximately 2 minutes, milk, oil, sugar, flour, and eggs then add cocoa, baking powder, salt and vanilla beat again till smooth.
Pour batter into the two prepared cake pans. Bake in pre-heated oven for approximately 30-35 minutes. Remove from oven and let cool completely.
In a small bowl add the warm water and the instant coffee (or brewed coffee), stir to dissolve. Place the Nutella in a small bowl and place the bowl over a small pot of boiling water let the Nutella thin so that it is easier to cover the cake (about 5 minutes). Place one of the cakes (slice off a little of the rounded top part of both cakes so they sit firmly on the plate) up side down on a serving plate and drizzle with a spoon the cake with 1/2 the coffee, cover with half the Nutella (or chocolate ganache, at this point I refrigerated the cake so that the Nutella (or chocolate ganache) would firm up, about 10 minutes). While the cake is in the fridge, in a medium bowl whip the cream and Mascarpone until very thick. Remove cake from fridge and cover with half the whipped cream. Place the second cake on top and spoon with the rest of the coffee and cover with the remainder of the Nutella (refrigerate again for 10 minutes), remove from fridge and cover with the rest of the whipped cream, sprinkle with cocoa or chocolate flakes if desired. Refrigerate for approximately 5-6 hours before serving or better yet overnight. Enjoy!** If you don' like Nutella you can always substitute with a chocolate ganache. In a heatproof bowl place 4 ounces chopped dark chocolate heat 1/2 cup whipping cream (or whole cream) to almost boiling then pour over chopped chocolate let sit for 10 minutes and then stir until smooth.