Creole sauce is a tomato-based sauce built on the Creole "holy trinity" of sautéed onion, celery, and bell pepper, seasoned with paprika, cayenne, garlic, thyme, and bay leaf.
It's served over rice, pasta, or seafood, and used as the base for dishes like shrimp Creole and étouffée. It's more heavily spiced than a plain tomato sauce or marinara, and typically includes the trinity base plus a splash of Worcestershire or hot sauce.
Regional versions vary in spice level and thickness; some cooks add tomato paste for a thicker consistency or simmer the sauce longer for deeper flavor.