Preheat the oven with electrical heat at 175 degrees Celsius.
Place a baking paper in a small baking form
Peel of the zest, and squeeze out the juice from the citrons. Or you can use already prepared ones.
Mix the flour, butter, sugar and the salt in a bowl.
In another bowl mix the egg, and lemon juice.
Add the flour mixture with the egg mixture.
Pour the batter in the baking form, and place in the middle of the oven for 30 minutes.
Take out the brownie and let it cool down.
Melt the margarine together with the chocolate in a casserole.
Take away the casserole from the stow and add the sugar and vanilla sugar and stir until the sugar is melted.
Add the lemon juice and zest ans mix well.
Let it cool down for 10 minutes and spread it evenly on top of the brownies.
Sprinkle the coconut flakes on top of the cake and place it in the fridge for minimum 2 hours.
Before serving it cut the brownie in squares.