Gather all your ingredients and equipment to ensure a smooth cooking process.
Heat your large heavy-bottomed pot over medium heat and add a splash of oil until shimmering.
Sauté the chopped onion, celery, and bell pepper until they soften and release a fragrant aroma, about 5 minutes. They should turn translucent and slightly tender.
Add the sliced smoked sausage to the pot and cook until it sizzles and begins to brown, about 3 minutes. This develops a smoky flavor and slight crispness.
Stir in the diced tomatoes and cook for another 2 minutes until they meld with the sausage and vegetables, creating a rich base.
Add the rinsed rice along with paprika, cayenne, and thyme. Stir well to coat the rice with spices and combine with the aromatic mixture.
Pour in the chicken broth and bring everything to a gentle boil, with bubbling and steam rising from the surface.
Reduce the heat to low, cover the pot, and simmer for 20-25 minutes. Keep an eye on it so the rice absorbs the liquid and becomes tender, with a slight smoky aroma filling the air.
Check the rice for doneness— it should be plump and tender, with a flavorful, slightly saucy consistency. If needed, cook a few more minutes uncovered to evaporate excess liquid.
Remove from heat and let the jambalaya rest, covered, for 5 minutes. This allows flavors to meld and the rice to finish absorbing the remaining juices.
Stir in the file powder, if using, for an earthy depth of flavor, and give everything a final gentle stir.
Serve your hearty Louisiana jambalaya hot, garnished with fresh herbs if desired. Enjoy the smoky, spicy flavors and tender rice with chunks of sausage in every bite!