Beat egg whites until stiff. Mix the butter, both types of sugar and egg yolks together until frothy. Mix the cinnamon, cocoa, chocolate, baking powder, flour, nuts and red wine into the batter. Fold in the egg whites.
Put the dough in a well-greased loaf pan. Bake at 180 ° C (fan oven 160 ° C, gas level 2) for 1 hour.
Then let it cool down and turn the cake out onto a wire rack. Melt the chocolate in a double boiler. Glaze the cake with a brush.