Step 1

Grease a 22cm springform pan.

Step 2

Melt 125 grams of the butter. Process biscuits in a food processor until fine crumbs, then stir in the melted butter. Press mixture into the base of prepared pan; refrigerate while preparing filling.

Step 3

Beat 100 grams of the butter (softened slightly), peanut butter and icing sugar mixture in a large bowl with an electric mixer until smooth and combined. Spread the mixture over the base and refrigerate.

Step 4

Chop the remaining 25 grams of butter. Place the butter and chocolate in a heatproof bowl over a pan of simmering water (do not allow base of bowl to touch water); stir until melted.

Step 5

Spread the chocolate over the peanut butter mixture. Refrigerate until ready to serve.