In the bowl of a stand mixer or a large bowl with a hand mixer, beat heavy cream on high until stiff peaks form, about 5 minutes. With a rubber spatula, gently fold condensed milk mixture into whipped cream. Stir in the peppermint extract and food coloring until well combined.
Pour half the ice cream mixture into a loaf pan. Break up cereal bars into small pieces and cover the top of the ice cream in the pan OR sprinkle 1.5 cups of Lucky Charms evenly on top. Pour the rest of the ice cream mixture over the cereal and then sprinkle more pieces of cereal bars or plain cereal on top.
Cover with plastic wrap or foil and place in the freezer until firm, about 6 hours.