10 ½oz.bag of marshmallowsminiature or full-size, about 6 cups
Optional: Valentine's Day sprinkles
Butter (or use cooking spray) a large, microwave-safe bowl.
Microwave 3 Tbsp. of butter with one 10 ½ oz. bag of miniature or full-size marshmallows for 1 minute on high. Remove from microwave, stir, and microwave again for an additional minute. Stir until smooth.
Gradually stir in 5 cups of Cheerios cereal. Fold in until the cereal is evenly mixed with the marshmallows.
Butter a 9 x 13″ baking pan.
Using your hands, the back of a spoon, or a rubber spatula, press the mixture into the baking pan. Allow to cool completely, then cut into bars.
Add sprinkles while still warm: If adding toppings like sprinkles, make sure to add them while the mixture is still sticky! Otherwise, they will not stick.
Let it harden before cutting: Let the mixture cool off in the pan before cutting into it for clean, even cuts.