You can buy
Rox's Roux online or you can make your own roux by reading my wife
Rox's story here. I prefer using shrimp or seafood stock to build flavor in this gumbo. For even added flavor, buy a small bag of dried shrimp and add to the stock. In this gumbo, the rich Creole flavors come from adding tomato paste and fresh okra – both of which are important in tying the cultures together. Along with roux, okra is a natural thickener in this gumbo. Some folks like to saute their cut okra to eliminate mucilage (slime), but with a long cooking time, it should be minimal.