Whip the eggs and sugar until foamy, then add the oil.

Sift in the cocoa, flour and baking powder.

Pour the batter into a greased and floured baking tray (about 38x25 cm) and bake in a preheated oven for about 10-15 minutes, checking with a toothpick.

Mix the pudding powder and sugar with a little of the milk set aside from the liter.

Bring the rest of the milk to a boil, then add the pudding mixture and stir until it thickens.

Add the dark chocolate to the hot mixture, and once melted add the Nutella.

Mix everything together, then cover with plastic wrap and let it cool until lukewarm, almost cold.

Whip the cream separately, then fold it into the cooled cream on the lowest mixer speed.

Pour the nougat cream over the sponge in the mold.

Place in the fridge for 30 minutes before making the ganache.

Heat the cream until boiling and pour it over the milk chocolate, stirring until melted (or melt in the microwave in 10-second intervals, stirring between each, until combined).

Pour the ganache over the cream and leave in the fridge overnight.

Sprinkle with chopped hazelnuts once cooled.