- Peel and slice onions. Heat olive oil in a wide skillet over high heat and add onions. Cook about 5 minutes, stirring often to keep the onions from burning. Reduce heat to medium-low and cook onions until brown, stirring occasionally (15 or 20 minutes).
- Sprinkle bison roast all over with salt and pepper and place in a slow cooker on high heat. Add chicken broth and 1 cup water. When the onions are cooked, scrape them into the roast. Add the wine to the skillet (if you’re using wine) and let it boil over high heat until reduced to about ½ cup. Add to roast.
- Turn heat to high and simmer 8 hours. Remove the roast — it will be falling-apart tender. If you like, combine juice, cooked potatoes and carrots on the stove and simmer for 20 minutes.