Chop peppers and onions and mix with seasoned salt and Italian dressing in a large plastic ziploc bag. Mix well, add tenderloin and marinate in refrigerator for 24 hours.
Remove medallions, wrap each border with a bacon strip and place on a baking dish.
Top each medallion with reserved seasonings, onion and peppers, and bake in a preheated 350-degree oven for 20 minutes. Be careful not to overcook and toughen the venison.