Cook the Turkey. In a large skillet over medium heat, cook the ground turkey, onion, bell pepper, and garlic until the turkey is no longer pink and the vegetables are tender.
Make the Sauce. Stir in the tomato sauce, ketchup, Worcestershire sauce, brown sugar, mustard, and seasonings. Simmer for 10-15 minutes, or until the sauce has thickened and the flavors have melded together.
Assemble the Sandwiches. Spoon the turkey mixture onto hamburger buns and serve hot.