Line a microwavable plate with a couple of paper towels. Add a layer of Cheerios.
Add a layer of hotdog pieces.
Microwave on high, between 1 and 1.5 mins. per hotdog, or until hotdog pieces are just a little crispy and Cheerios have absorbed some of the hotdog juices. (Katie says, "Mmm . . . hot dog juices . . .")