Preheat the oven at 175 degrees Celsius.
Cover the bottom of a baking form with baking sheet.
Start by making the cake. Melt the butter and chocolate in a sauce pan. Put the sauce pan on the side.
Whip the sugar and eggs white and fluffy.
In the sauce pan add the sugar mixture and stir gently.
Mix the baking powder and flour. Add in the batter and mix gently together.
Butter the baking form. Add flour evenly
Pour the batter in the baking form. Place in the middle of the oven for 20 minutes.
Take out the cake and let it cool down.
Time to make the truffle frosting.
In a sauce pan pour the heavy cream. When it starts to boil turn off the heat.
Add the dark and milk chocolate and stir until fully melted.
Spread evenly over the cake.
Place the cake in the fridge over the night.
Decorate the cake before serving time.