In a large skillet over medium heat, brown the sausage for about 5 minutes until caramelized. Add diced onion, celery, and bell pepper, sautéing until softened, then stir in minced garlic and add rinsed rice. Toast rice for about 2 minutes before adding chicken broth along with Cajun seasoning, thyme, salt, and pepper. Bring to boil, cover, and reduce heat to low for 18-20 minutes until rice is tender.

Soak catfish fillets in buttermilk for at least 15 minutes. In a bowl, combine cornmeal, flour, and spices. Heat oil in a deep skillet to 350°F. Coat each catfish fillet in the cornmeal mixture, then fry for 3-4 minutes per side until golden brown. Drain on paper towels.

In another sauté pan, melt butter over medium heat, add diced onion and bell pepper, cooking until soft. Stir in minced garlic, crawfish tails, and diced tomatoes, simmer for 2-3 minutes. Pour in heavy cream and let bubble gently for 3-5 minutes until it thickens. Season with salt and pepper.

On each plate, layer dirty rice as the base, place two crispy fried catfish fillets on top, and drizzle crawfish cream sauce over the fish. Garnish with freshly chopped parsley or sliced green onions.