1) Combine the butter, peanut butter, sugar, rice cereal and chocolate chips together in a bowl. Roll the mixture into 2 1/2-cm balls and place onto a parchment lined baking sheet in the freezer.
2) Melt the milk chocolate chips in a heatproof bowl set over a saucepan of simmering water, stirring often, until smooth. With a fork, dip the frozen balls into the melted chocolate. Place on a cool baking sheet lined with parchment paper. Place in freezer for 5 to 10 minutes until the chocolate has set. Store the balls in an airtight container at room temperature.