1) In a large skillet heat oil along with the butter on medium-high heat. Add onions and cook until translucent. Add the minced garlic and turkey. Cook turkey until no longer pink. Make sure to break up the crumbles. Add the rest of the ingredients except for the green peppers.
2) Turn the heat to simmer. Cook for 2 hours stirring once every 15 minutes. Add the peppers 20 minutes before turning off the heat. Adjust for seasoning. Serve on buns.