Add marshmallows. Stir until melted, then removed from heat.
Add rice cereal, stir until marshmallow mixture and cereal are combined.
Allow rice and marshmallow mixture to cool for two minutes.
Add Peeps and stir to combine.
Grease a 9x13 inch pan. Press mixture into pan, and allow to cool before cutting.
Notes
Peeps get very sticky when you're cutting them. I used a kitchen scissors, and wiped the scissors clean with a wet cloth between each Peep. 2 cups of Peeps is about 8 Peeps in total.