In a sauté pan, or flat iron grill, melt a little butter and sprinkle in some celery salt. Slowly cook the onions and peppers. The heat should be low enough that they start browning around the 15 minute mark.
Cook your hot dogs. I prefer flame grilled for that little bit of crunchy seared skin, but boiling and steaming also works.
Put your hot dog in the bun, smother with the grilled peppers and onions. Add relish, mustard, and sport peppers.
Finish with a small sprinkle of celery salt