Shape into a log on clingwrap and place in freezer for about 1 hour.
Once frozen (not totally), remove the clingwrap and cut rounds of 1/2 cm (or less, depending on how good your knife skills are and how frozen the dough is).
Place the rounds on a tray lined with baking paper and chill in the fridge or freezer for 1 hour.
Spread peanut butter on one of the rounds and top with another until all rounds are used up.
Keep in the fridge or freezer - they are really yummy frozen!