The original recipe made an absolute ton of brownies (even too much for me), so my mum kindly scaled the recipe down to a more manageable size.
To make the brownies simply melt 150g butter withe 100g of dark chocolate (in a microwave or over a pan of simmering water). In a separate bowl mix together 40g coco powder, 30g of flour, 270g of sugar and 1teaspoon of baking powder and then add this to the chocolate mixture. Beat three eggs (free range) and add them to the mixture. Pour into a prepared tray and bake at 180 degrees (about 150 for a fan oven) for about 20 minutes. Make sure you keep checking them though as then can cook a lot quicker than you might think. The secret to a good brownie is to take them out a little bit before you think they are ready, that way the will stay all lovely and gooey.