Set a heatproof bowl over a pan of barely simmering water. Add the peanut butter and the chocolate and stir until melted and smooth.
Add the peanuts and stir to coat well. Drop by rounded spoonfuls onto a waxed paper lined baking sheet and chill until firm, about 30 minutes. (You can make them as big or as small as you like. I made mine into 24 clusters.)