Prep time - 40 minutes Cooking time - 16 minutes Step 1 Step 2 Step 3 Step 4 Step 5 285 grams/6.5 OZ unsalted butter, room temperature 310 grams/11 OZ of powdered sugar 210 grams/7 OZ plain flour 375 grams/ 13 OZ smooth peanut butter 100 grams/3.5 OZ dark chocolate chips 120 grams/4 OZ thickened or heavy cream 1 tablespoon vanilla extract Preheat the oven to 160C/320F In a large bowl, beat 70 grams/2.5 OZ butter until pale and creamy Sift in 90 grams/3 OZ of powdered sugar, add vanilla extract and beat again Sift in 200 grams/7 OZ flour and stir gently until a buttery dough forms Put the dough into cake tin. Press it down to form a smooth layer. Make small holes with a fork Bake for 15-16 minutes or until golden brown. Leave to cool In a large bowl, combine 115 grams/4 OZ butter, 220 grams/8 OZ powdered sugar and 375 grams/13 OZ smooth peanut butter Beat it with a mixer until the mixture is smooth Pour the mixture over shortbread crust. Spread out evenly and refrigerate until it's firm Place 100 grams/3.5 OZ dark chocolate chips in a heatproof bowl In a small saucepan, warm 120 grams/4 OZ heavy cream until simmering, but not boiling Pour the warm cream over the chocolate Whisk until the consistency is smooth Pour the melted chocolate over peanut butter filling Microwave couple spoons of peanut butter until melted Drizzle the melted peanut butter over chocolate in long lines Use a toothpick or a wooden skewer to create swirly pattern Put into fridge for at least an hour to set