Line a cookie sheet or 9x13 inch pan with wax paper and spray with non-stick spray.
Heat butter in a large pan until the butter has melted.
Add in the marshmallows and stir until completely smooth.
Combine Malt-O-Meal® Tootie Fruities® cereal and melted mixture in a large bowl and stir until combined.
Pour mixture into lined and sprayed cookie sheet and even out using damp hands.
Allow bars to harden for a few hours before cutting and serving.