Dice the onion, celery, and bell pepper into uniform 1/4-inch pieces, mince the garlic, and slice the andouille sausage into 1/4-inch rounds. Set all ingredients aside in separate bowls. Preheat your oven to 350°F. In a small bowl, combine the dried thyme, dried oregano, Cajun seasoning, and cayenne pepper—this ensures the spices distribute evenly throughout the dish rather than clumping in one spot.

Heat a large, oven-safe skillet or Dutch oven over medium-high heat. Add the ground beef and cook, breaking it apart as it browns, for 5-7 minutes until no pink remains. Add the sliced andouille sausage and cook for another 2-3 minutes to release its flavorful oils. I like to brown the sausage with the beef rather than separately because it seasons the entire pot and creates a more cohesive flavor foundation. Drain excess fat if needed, leaving about 1-2 tablespoons in the pan.

Add the diced onion, celery, and bell pepper to the browned meat and cook over medium heat for 5-7 minutes, stirring occasionally, until the vegetables begin to soften and release their aromas. Add the minced garlic and cook for 1 minute more until fragrant. Pour in the spice mixture from Step 1 and stir constantly for about 30 seconds to toast the spices slightly and deepen their flavors. This technique, called blooming spices, ensures they infuse the oil rather than remain raw-tasting.

Stir in the long-grain white rice and toast it in the pan for 1-2 minutes, stirring constantly—this helps the rice absorb flavors and prevents mushy results. Pour in the canned diced tomatoes with their juice, hot sauce, Worcestershire sauce, beef broth, and chicken broth. Stir well to combine and ensure the rice is mostly submerged. The combination of beef and chicken broth creates a balanced, rich base without being overly heavy.

Cover the skillet or Dutch oven tightly with foil (or a lid if using a Dutch oven) and transfer to the preheated 350°F oven. Bake for 40-45 minutes, until the rice is tender and has absorbed most of the liquid. I recommend checking at the 40-minute mark—if there's still excess liquid but the rice is done, remove the foil and let it cook uncovered for a few minutes to evaporate the moisture. The gentle, dry heat of the oven allows all the flavors to marry while cooking the rice evenly.

Remove the jambalaya from the oven and let it rest, covered, for 5 minutes. This allows any remaining liquid to be absorbed and keeps the rice fluffy. Fluff gently with a fork before serving. Taste and adjust seasonings if desired—a touch more hot sauce or Worcestershire can brighten the flavors if needed.