1. Lightly grease a 19cm x 29cm rectangular pan. Line base and two long sides with baking paper.

2. Combine butter and chocolate in a heatproof bowl; place bowl over a pan of simmering water, stirring, until melted. Remove from heat, transfer to a large bowl.

3. Stir sugar, eggs, flour and choc bits into chocolate mixture until combined. Pour mixture into pan.

4. Cook in a moderate oven, 180oC, for about 35 to 40 minutes or until firm to touch. Cool in pan; cut into rectangles.

5. Serve brownie dusted with sifted cocoa powder.

Hint. Brownies can be made up to 4 days ahead; store in an airtight container. Or freeze for up to 2 months; thaw at room temperature.