Step 1

Preheat fan-forced oven to 160C. Line a tin with baking paper.

Step 2

Using an electric mixer, cream butter and brown sugar until light and fluffy.

Step 3

Add eggs one at a time and beat on low speed.

Step 4

Mix through flour and cocoa.

Step 5

Pour mix into prepared tin.

Step 6

Place small spoonfuls of peanut butter on top of mixture. Use a knife to swirl the peanut butter through the brownie mixture until you have a rippled effect.

Step 7

Bake in pre-heated oven for 20 minutes.