These brownies are very rich and fudgy. If you prefer them more of a cakey texture, just add an extra quarter teaspoon of baking powder, and bake for 5-10 more minutes.
As always, the better quality ingredients you use, the better the outcome, so please go for real butter and decent quality chocolate if you can. However, cheap supermarket chocolate and baking blocks such as Stork still give a thoroughly decent brownie.