Line the base of a loaf tin with an over-sized sheet of baking paper (large enough to cover the bars).

Place the ingredients in a large bowl and stir until well combined. The mixture should resemble a thick dough. If it’s too runny, stir in some more cocoa powder.

Transfer the mixture to the tin.

Fold the excess sheet of baking paper over the mixture and press down into the base of the tin. Flatten the surface of the mixture using your hands.

Uncover the mixture and neaten up the edges of the bars with a spatula. Cover and refrigerate until firm.

Store any leftovers in an airtight container and refrigerate for up to 4 days or freeze on same day.