Add oil to a large pan over low to medium heat and sweat the peppers and garlic for 5-7 minutes, stirring frequently.
Add in the ground beef, turn the heat to medium and cook until all of the pink is gone, about 7-9 minutes.
Next, pour the tomato puree, mustard, brown sugar, Worcestershire sauce, vinegar, tomato paste, and chili powder and simmer over low heat for 25-30 minutes.
Finish by stirring in salt and pepper and serve on buns with optional toppings.
