For the quick 1 to 1 cake, weigh the eggs with a scale. Add equal amounts of sugar to the weight of the eggs. Cream sugar and eggs well until mixture is white. Stir 25 g chocolate chips into batter, if desired. Fold in same amount of flour as eggs.
Grease and flour the mold well. Spread the batter evenly in the pan and bake in the preheated oven at 180 °C top/bottom heat for approx. 40 minutes.
Turn out of the pan and let cool.
Melt butter and chocolate in the microwave at 750 watts for 1.5 minutes, stir well and microwave again for 30 seconds. Mix remainder by hand, pour over cake and decorate as desired. Serve the quick 1 to 1 cake with whipped cream.