Instructions

1. Grease and line an 8 inch square tin, ensuring two sides of the baking paper overhang. In a food processor, crush the graham crackers or plain biscuits until they resemble fine crumbs. Pour in the melted butter and give it a good stir until the biscuits are moist and stick together when pressed with your finger. Place the biscuits into your prepared tin and press down using the back of a spoon until you have a nice even layer. Pop into the fridge.
2. Pop the butter and chocolate in a heatproof bowl and place over a medium saucepan that is filled with a bit of water, say 5cm (2 inches) high or so . You need to ensure the bowl will not touch the water below. Place on the stove on medium heat and stir while the chocolate and butter melt. Once completely melted, remove the bowl from the heat and leave to cool slightly. Meanwhile grab the crust from the fridge and line the Twix bars on top of the biscuit and then put it back in the fridge.
3. Preheat oven to 180 C (350 F) standard / 160 C (320 F) fan-forced.
4. Next, add the sugar and vanilla to the chocolate mixture and beat with an electric beater until combined. Add the eggs, one at a time and beat throughly. Then sift in the flour and beat until mixture is smooth. Pour the mixture into the prepared tin over the Twix bars. Very gently smooth over the top.
5. Bake the brownie for about 50 minutes or until cooked through. It should have a nice cracked top and no longer wobble in the middle. Leave to cool completely before removing from the tin and cutting into squares. Best served slightly warm with whipped cream or ice cream. The brownies will keep well in an airtight container for 3 days. Just microwave the brownie for 10-15 seconds to serve warm.