2) Place the peanuts in a shallow dish or on a plate. Melt the chocolate in a heatproof bowl set over a saucepan of slightly simmering water, over the lowest possible heat, stirring frequently. Make sure the water does not come into contact with the bowl at all. Pour the melted chocolate into a tall glass. Dip each frozen banana into the chocolate, turning it to coat, and immediately roll in the peanuts.
3) Place on a tray covered in waxed paper. Serve immediately or wrap individually in plastic wrap or waxed paper and freeze for up to two weeks.