• 5 tablespoons butter
• 5 tablespoons all-purpose flour
• 1 yellow onion, chopped
• 1 green bell pepper, chopped
• 2 stalks celery, chopped
• 4 cloves garlic, chopped
• 2 tablespoons Cajun seasoning, divided, or to taste
• 1 teaspoon cayenne pepper (optional)
• 2 cups fish stock
• salt and ground black pepper to taste
• 1 pound cooked crawfish tail meat

Melt butter in a Dutch oven over medium heat. Stir in flour to make the roux, and stir continuously until roux is at least the color of peanut butter, about 10 minutes, or for a darker roux, 15 to 20 minutes. Add onions, bell pepper, celery, and garlic; cook and stir for 5 to 7 minutes. Stir in half the Cajun seasoning, cayenne pepper, and stock. Season with salt and ground black pepper. Reduce heat to low and simmer for 15 minutes. Stir in crawfish, turn heat off, and cover. Let stand until crawfish are heated through. Taste and add remaining half of Cajun seasoning, if needed.