1. Heat oil in a large frying pan over medium heat, add onion, and cook until deep golden and very tender, stirring frequently, about 20 minutes.

2. Meanwhile, heat grill to medium (350° to 450°). Grill hot dogs until slightly charred all over, about 6 minutes, turning occasionally. Add buns and grill, turning frequently, until warmed and lightly charred, about 3 minutes.

3. Spread buns with mayonnaise and drizzle with mustard and barbecue sauce. Set hot dogs in buns.

4. Sprinkle cheese on top, followed by caramelized onions and bacon.

*Find bison hot dogs at highplainsbison.com or Whole Foods Market.