Preheat your oven to 350ºF. This is an essential step to ensure your casserole bakes evenly and thoroughly. While the oven heats up, you can prepare your ingredients, so they’re ready to go.
Lightly spray a 9×13-inch baking dish with cooking spray. This helps to prevent the casserole from sticking and makes for an easier cleanup later. Make sure to cover the dish well to ensure the casserole slides out smoothly once it’s baked.
In a large skillet, cook the smoked sausage over medium heat until it starts turning golden brown. This caramelization process develops a depth of flavor that enhances the overall taste of the dish. Stir frequently to prevent the sausage from burning.
Add the Zatarain’s Dirty Rice mix along with the water called for in the package instructions. This is where the magic begins! Stir everything together and prepare the dirty rice according to the package directions. The rice will soak up all those delicious flavors.
Once the dirty rice is cooked, remove it and the sausage from heat. Allow it to cool slightly while you gather the remaining ingredients.
Stir in the rinsed red beans, cream of chicken soup, and sour cream into the rice and sausage mixture. Make sure to combine everything thoroughly, so every bite is packed with flavor. The mixture should be creamy and well-blended.
Spread the rice mixture evenly into the prepared baking dish. It's important to ensure that it’s spread evenly to promote even cooking. Take your time with this step to get it just right!
Top the casserole with the French fried onions, sprinkling them generously across the top for a crispy finish. This adds another texture to the dish that you and your guests will love.
Bake uncovered for 30 minutes, until bubbly. Keep an eye on it, as oven temperatures can vary. You want it to be hot throughout and the top golden brown.
