Heat the vegetable oil in a large heavy saucepan over medium-high heat. You want the oil to shimmer but not smoke. This means it’s hot enough to start cooking your chicken.
Once the oil is hot, add the chicken pieces, cooking until they’re no longer pink, which takes about 5 to 7 minutes. Remove them from the pan and set aside, allowing the flavors to enhance the gumbo later.
Next, drop in the salted butter and let it melt, swirling it in the pan. Then, whisk in the all-purpose flour to create a roux. This step is crucial, so keep stirring!
Lower the heat to medium or medium-low. Cook the roux, stirring frequently for 30 minutes to one hour, until it reaches a dark chocolate brown color. This deep color adds a rich flavor to your Easy Gumbo.
Once your roux is dark enough, stir in the celery, yellow onion, and green bell pepper. Sauté these veggies until they’re nearly fork-tender, about 5 minutes. The aroma will be heavenly!
Season the mixture with the Cajun seasoning and garlic salt, stirring well to combine. Allow the flavors to meld for a few moments.
Gradually add in the low sodium chicken broth, one cup at a time, while stirring constantly. Make sure the sauce thickens before adding more; this ensures a rich texture.
Bring the mixture to a gentle simmer, uncovered. If the sauce is still a bit thin, let it cook for 5 to 10 more minutes until it thickens slightly.
Once thickened, return the cooked chicken and add the andouille sausage back into the pot, allowing it to simmer together.
Finally, add in the raw large shrimp. Cook until the shrimp curl and turn opaque, about 5 minutes. This adds a delightful seafood element to your Easy Gumbo.
Plate your gumbo warm, and if desired, serve it over rice with a sprinkle of green onions on top as an optional garnish. Enjoy every delicious bite!