1. 1. Pat chicken dry and cut into 1/2-inch cubes.

2. 2. Heat olive oil in a large skillet or Dutch oven over medium-high heat. Add onion and bell pepper. Cook, stirring occasionally, for 5-7 minutes until softened.

3. 3. Stir in minced garlic and Cajun seasoning. Cook for 1 minute, stirring constantly, until fragrant.

4. 4. Add cubed chicken to the skillet. Cook, stirring frequently, until browned on all sides and mostly cooked through, about 5-7 minutes.

5. 5. Pour in diced tomatoes (with juices), tomato paste, chicken broth, Worcestershire sauce, and brown sugar. Stir well, scraping up any browned bits from the bottom of the pan.

6. 6. Bring mixture to a gentle simmer. Reduce heat to medium-low, cover, and let cook for 10-15 minutes, until sauce thickens and flavors meld. If too thick, add a splash of broth; if too thin, simmer uncovered for a few minutes.

7. 7. Taste and adjust seasonings (salt, pepper, more Cajun seasoning).

8. 8. Optional: Toast buns on a skillet or under the broiler for 1-2 minutes.

9. 9. Spoon generous amounts of the chicken mixture onto buns. Garnish with cilantro or parsley if desired. Serve immediately.