In a large Dutch oven, melt the butter until frothy and browned. Season the bison pot roast with salt and pepper. Then sear the bison pot roast until browned, about 2-3 minutes per side. Remove from the pot and set aside. It will not be cooked all the way through.
Preheat the oven to 225 F. In the remaining butter in the pot, saute the onions, carrots, garlic and pepperoncini peppers. Stir in the pepperoncini juice and au jus mix.
Place the pot roast back into the pot and gently press into the veggies. Add the Worcestershire, onion powder, garlic powder, dill, parsley and bay leaves along with the beef broth to the pot. Cover and cook for four hours.
After four hours, remove the pot from the oven. Remove the bay leaves. Turn up the oven temperature to 350 F. Shred the bison pot roast with two forks. It should shred easily.
Return the pot roast to the oven, uncovered, and continue cooking for another hour, until the liquids have reduced by half. Serve over mashed potatoes and enjoy!
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