Stir gently until homogeneous and transfer the mixture into a greased baking tray. Bake this thick cake layer for about 15 minutes in a preheated 392°F (200 °C) oven. Then reduce to 356°F (180 °C) and bake for another 20 minutes.
To prepare the cream mixture, combine the cream and milk and put them to boil. Crumble the chocolate in a large pot, pour in the hot milk mixture and stir until homogenized.
Cut the baked cake layer into 3 parts, bind them with cream and coat the entire cake with cream on top. Set aside a portion of it (about 1/4). Put the truffle cake for 1 night in the refrigerator to harden.
Then melt the separated cream lightly in a water bath and pour it over the cake.