Preheat the oven to 170°C
Melt the butter and allow to cool.
Using an electric mixer, beat the eggs with the sugar until smooth and creamy, then stir in the cooled butter. Sift the flour and cocoa into a large bowl and gradually stir into the egg mixture until smooth.
Pour into the baking tin (approximately 33 x 23 x 5 cm), lined wit baking parchment and bake for 35-40 minutes until the centre is cooked. (If height is less than 4cm, bake it for a shorter time.) Remove from oven and allow to cool slightly. Once cool remove the brownies from the baking tin and allow to cool further.
Beat the butter at high speed until the mixture becomes pale and fluffy. Add the icing sugarand sifted cocoa and beat again until smooth and creamy. At this stage the icing is ready for use.
Cut the brownie cake into cubes and stack them into a tip-truck. Place the icing in buckets. Grab some cement trowels and teach your kids how to make their very own chocolate brick wall.
This one is loads of fun!
