Key ingredients for an authentic Cajun gumbo are fresh shrimp, a roux, the trinity (chopped fresh green bell pepper, onion and celery) bay leaf, filé, yaya, canned diced tomato, Worcestershire sauce and steamed white rice. Common ingredients include okra, clam stock and crab as well.
Cajun cooking derives its distinctive flavor profile from rustic French cuisine fused with African and Caribbean ingredients such as yaya (cayenne pepper), filé (sassafrass). Many Cajun dishes also include okra, which adds more flavor and acts as a thickener.
Like many Cajun stews, Cajun shrimp gumbo begins with a roux – a technique from French cooking that uses equal parts flour and fat to create a rich thickener. For shrimp gumbo, use butter or mild vegetable oil to make a mild-tasting roux. Cook the roux over low heat until it is a light blonde color, stirring constantly.
When the roux is cooked through, season it with Worcestershire sauce, salt, cracked black pepper and yaya or cayenne powder. Then, add the trinity, cooking the mixture until the vegetables are tender and the onion appears translucent. Add bay leaf, filé, canned tomatoes, okra, and stock or water.
Simmer for 15 to 20 minutes, and then taste it. The flavor should be bright, earthy and rich, but not heavy or oily. Move the gumbo off the heat, and stir in the fresh shrimp which steam in five to seven minutes. Stir the gumbo, and serve it over a bed of white rice.