Place the biscuits (or graham crackers if used) into the bowl of a food processor and blend until crumbs form. Add peanut butter and melted butter and process until completely combined and the mixture holds together.

Slightly grease a 8×8 inch (20x20cm) square pan and line with parchment paper, in such a way that some edges are longer to make it easy to lift it up once it's set.

Spread the peanut butter mixture into the prepared baking pan and press with the back of the spoon to create a smooth surface.

Melt chocolate and 2 tbsp (30g) of creamy peanut butter over bain marie, over low heat. Stir until smooth. Meanwhile place the other 2 tbsp (30g) of peanut butter into a small sauce pan over low heat and stir until melted and smooth. Spread the chocolate over peanut butter layer. Add teaspoons of melted peanut butter on top and with a knife create swirls on the surface.

Refrigerate for 2 hours to set. Let it sit 10 minutes at room temperature before cutting. Bars can be frozen well. Enjoy!