Step 1

Preheat oven to 350°F. Heat butter and oil in a large Dutch oven over medium-high, stirring occasionally, until butter is melted, about 1 minute. Add chicken; cook, stirring occasionally, until lightly browned on all sides, about 8 minutes. Using a slotted spoon, transfer chicken to a plate lined with paper towels. Add sausage to Dutch oven; cook, stirring occasionally, until well browned, about 6 minutes. Transfer sausage to plate with chicken. Do not wipe out Dutch oven.

Step 2

Add onion, bell pepper, and celery to Dutch oven; cook over medium-high, stirring often, until tender, about 5 minutes. Add garlic and Creole seasoning; cook, stirring constantly, until mixture is fragrant and lightly browned, about 1 minute.

Step 3

Return browned chicken and sausage to the pot, and stir in tomatoes, broth, rice, salt, thyme, pepper, and bay leaves. Bring to a boil over high, and stir in shrimp. Cover Dutch oven, and transfer to oven. Bake until rice is tender and chicken and shrimp are cooked through, 20 to 25 minutes. Remove from oven; gently stir jambalaya to evenly redistribute any liquid. Garnish with scallions and serve.