Procedure:
Break 200 g chocolate and melt it in a double boiler. Turn on the oven. Soften 200g butter in a bowl using an electric mixe, add the sugar and the eggs. Knead slowly.
Pour the yogurt and flavor with rum, and mix well the mixture with a spatula. Sift the flour and add it to the mixture, also add the cocoa and baking powder. Mix the ingredients well. Finally add the melted chocolate. Pour the mixture into the mold. Bake and cook for about 45 minutes, use a toothpick to see if the dough is cooked.
Leave to cool before turning out. Meanwhile, prepare the glaze. Combine in a glass bowl the remaining butter, the remaining chocolate and funds the two ingredients in a double boiler. Combine the icing sugar mixture and mascarpone. Stir gently and make it cool to get a soft frosting.
Put the cake on a shrug, pour on the top the frosting, and cover the entire cake. The New Year's cake is ready.