First of all, make a full pan** of Rice Krispie treats, recipe linked in the ingredients.
Once you’ve partially mixed together the melted marshmallows with the Rice Krispies cereal, stir in the M&M’s candies and finish mixing everything together.
Spread the Rice Krispies treats mixture into a pan.**
Immediately sprinkle on Valentine heart shaped sprinkles, so they'll stick to the still warm marshmallow treats.
Cut heart shaped Rice Krispie treats with a heart shaped cookie cutter.*** Work your way around the edge, then in toward the middle.
And that's it. They're ready to serve and enjoy!