For the filling:

1 lb ground chicken (93 percent lean)

1 tbsp olive oil

1 medium yellow onion, diced

2 stalks celery, diced

1 green bell pepper, seeded and diced

3 cloves garlic, minced

2 tbsp Cajun seasoning

1 cup crushed tomatoes

1/2 cup tomato sauce

1 tbsp Worcestershire sauce

1 tsp brown sugar

1/2 tsp salt

1/4 tsp black pepper

For serving:

5 brioche buns, split

2 green onions, sliced