In order to prepare for the baking of brownies preheat the oven to 350º F (180º C). Then make sure you line the cake tin with non-stick paper. The next step is to grease the tin with some butter.
In a medium bowl beat the 3 eggs and mix them with sugar and the extra vanilla. Furthermore, add the salt, cocoa powder, flour and baking powder as well as the melted butter. If you wish to crown the mixture with some delicious nuts do it now.
Bake the brownies for at least 25-30 minutes until you think it's ready. For an extra trick you can also use a wooden pick to control the texture of the mixture. If it comes out almost perfectly clean, the brownies are ready to be taken out from the oven. Let the cake cool and apply a tiny amount of sugar powder on the top to make it even more delicious.