Preheat the oven at 175 degrees Celsius.
Melt the margarine together with the chocolate in a casserole. Take it away from the stow and let it cool down for 5 minutes.
Add the eggs, vanilla sugar, flour, baking powder and the sugar and stir it all well.
Cover the bottom and edges on a baking form approximately 20 x 30 cm and pour the batter evenly on it.
Place the cake in the oven for 25 minutes. Take it out and let it cool down, and cut the brownie in small squares before serving it.