Ingredients
Method
Grease a 18cm x 28cm rectangular slice pan. Line base and sides with baking paper, extending paper 4cm above pan edges.
Combine chocolate and butter in a large heatproof bowl. Sit bowl over a saucepan of simmering water. Stir until melted and smooth. Remove. Cool slightly. Whisk in sugar, then eggs.
Sift flours and cocoa over chocolate mixture. Stir until combined. Pour into prepared pan. Spread evenly.
Make topping, combine sour cream and spread in a small bowl. Dollop teaspoons of the mixture over brownie in pan. Using a flat-bladed knife, swirl mixtures together to create a marble effect.
Cook in a moderately slow oven (160C) for 35 to 40 minutes, or until just firm to touch. Remove. Cool in pan.
Lift brownie from pan. Cut into squares. Serve with cream. Drizzle with extra warmed Biscoff.