Using an electric whisk, mix the eggs and both sugars for about 10 minutes until thick, pale and doubled in volume.
Meanwhile, place the chocolate and butter in a bowl, and suspend over a saucepan of simmering water (a bain-marie) do not allow the bowl to touch the water, until the chocolate has melted.
Remove from the heat and whisk in the sieved flour and baking powder, making sure there are no lumps in the mix.
The eggs should now be ready, so fold half the mixture into the chocolate, and then the remaining half.
Pour into the pre-lined baking tray and put in the preheated oven for approximately 20-30 minutes. When you shake the tin it should only have a slight wobble.
Remove from the oven and allow to cool. Best to chill in the fridge for 2-3 hours before serving.notes: Be careful not to overcook the brownies or they will turn from fudgy to cakey. I always use large eggs for baking, but this recipe calls for medium. The choice is yours.I dusted by brownies with cocoa powder, but this is optional
