This Whole30 chicken fajita casserole is a low carb, gluten free and paleo meal that is easy to make and sure to be a hit! It’s packed with all of the chicken fajita flavors you love and full of fresh and healthy ingredients like shredded chicken, bell peppers, cauliflower rice, and onions – all wrapped up in a casserole dish! It’s perfect for both a weeknight dinner and for meal prep for lunches. This delicious Whole30 casserole is a must try.
Whole30 Chicken Fajita Casserole Ingredients
For the chicken fajita casserole you will need 1-1.5 pounds of shredded chicken that’s already cooked. Using leftover chicken or a rotisserie chicken is easy since it’s the quickest way to get right to cooking the casserole, and this is a great way to use up leftover chicken. However, if you don’t have cooked chicken already, you can poach it in a pot of boiling water for about 10-15 minutes while you prep the rest of the casserole.
Beyond the chicken you need 20 ounces of frozen cauliflower rice, one sliced red onion, and a red bell pepper, and a green bell pepper, both sliced. To make the sauce you need a cup of chicken broth, a half cup of canned coconut cream, and 2 tablespoons of arrowroot flour (dissolved into a half cup of water).
For the coconut cream, make sure that hard part that sometimes forms at the top is mixed in with the liquid. They can sometimes separate in the can depending on the brand or the temperature they’re stored at. You can mix them easily by just shaking the can prior to opening it.
You will also need 3 tablespoons of fajita seasoning. We have a recipe for that here if you want to keep some on hand like I do or you can make enough for this recipe with chili powder, cumin, garlic powder, paprika onion powder, salt, and pepper in the amounts in the notes below.
All of these ingredients for your Whole30 chicken fajita casserole are easily accessible at major grocery stores. This is a really short ingredient list, and the few pantry items like the chicken broth, arrowroot, canned coconut cream and spices could also be purchased online at retailers like Amazon or at a discount from Thrive Market (new members save 40% off their order!).
How to Cook Chicken Fajita Casserole
To begin, you’ll preheat the oven to 400 degrees F. In a large casserole dish, add the shredded chicken and cauliflower rice. Slice the onion and bell peppers taking note to keep the slices similar sizes so they cook evenly. Then add them to the casserole dish with the chicken and cauliflower. Mix everything together until evenly dispersed.
Next, over high heat and in a large skillet, combine the chicken broth, coconut cream (see note in recipe), and fajita spices. Whisk the sauce until it’s fully combined and bring to a simmer for about 8 minutes to let the sauce reduce. In a small bowl, use a fork to dissolve the flour into the water. Once it is fully dissolved pour it into the sauce and begin whisking immediately so it doesn’t clump. The sauce will begin to thicken and the simmer will change to a slower bubble.
Now pour the sauce over the mixture in the casserole dish. Give it a toss and evenly coat the chicken and veggie mix. Once its fully combined, flatten it into an even layer in the casserole dish with the back of a spoon or spatula. Place the chicken casserole into the oven for about 35-40 minutes until the veggies on top look baked.
Serving and Storing Instructions
To serve your chicken fajita casserole, let it rest first for a few minutes, and then gather your optional toppings. Those optional toppings include, but of course aren’t limited to, cilantro, green onions, lime, avocado, guacamole, and/or pico. If you’re not keeping this Whole30, feel free to sprinkle shredded cheese to the top of the casserole in the last 5 minutes of baking, and serve with options like sour cream.
To store the chicken fajita casserole, you’ll want to let it cool completely. Then place the casserole into an airtight container or individual meal prep containers. It’ll keep in the refrigerator for about 4 days. I don’t recommend freezing this casserole because reheating the already cooked cauliflower rice can make it too watery.
Alternatives or Substitutions
If you want to add more vegetables so substitute any of them out, you can add black olives, sliced jalapeños, a 14 ounce can of drained diced tomatoes, a 4 ounce can of diced green chiles, or a diced poblano pepper.
If you like you can also use a mix of cauliflower rice and quinoa if you’re not trying to keep this casserole Whole30/paleo. You could also use a cooked brown rice and cauliflower rice blend. Another great addition is a can of rinsed and drained black beans. The chicken fajita casserole will still be gluten free and delicious whichever way you go!
Other Healthy Casserole Recipes You’ll Love:
- Jalapeno Buffalo Chicken Casserole
- Big Mac Casserole
- Creamy Sausage & Potato Casserole
- Southwest Ground Beef Casserole
- Chicken Alfredo Spaghetti Squash Casserole
- 1–1.5 pounds cooked and shredded chicken
- 20 ounces frozen cauliflower rice
- 1 red onion, sliced
- 1 red bell pepper, sliced
- 1 green bell pepper, sliced
- 1 cup chicken broth
- 1/2 cup canned coconut cream (see notes)
- 3 tablespoons fajita seasoning (or see notes for individual spice measurements)
- 2 tablespoons arrowroot flour dissolved in 1/2 cup water
- Optional: 1 (14 ounce) can drained diced tomatoes (drain well)
- Optional for topping: cilantro, green onion, limes, avocado, guacamole, pico
- Preheat the oven to 400 degrees F.
- Add the shredded chicken, frozen cauliflower rice, sliced red onion and sliced bell peppers to a large casserole dish and toss to combine (add diced tomatoes if using)
- In a large skillet over medium high heat, add the chicken broth, coconut milk and fajita spices. Whisk to fully combine and bring to a simmer. Let simmer for about 8 minutes to let the sauce reduce
- Use a fork to dissolve the flour in a small dish with the water. Once fully dissolved and mixed into the water, pour it into the sauce. Whisk immediately to prevent clumping. The sauce should begin to thicken immediately and the simmer will change to a slow bubble
- Remove the sauce from the heat and pour it into the casserole dish. Toss again to mix the sauce into the chicken and vegetables. Once fully coated in the sauce, flatten out the chicken and vegetables so it’s in an even layer in the dish
- Place the casserole into the oven and bake for 35-40 minutes, or until vegetables on top look baked
- Remove from the oven and garnish with any optional toppings. If not keeping this Whole30 or dairy-free, sprinkle a bit of cheese over the top in the last 5 minutes of baking
- Gluten-free 1:1 flour can be used in place of arrowroot if not keeping this Whole30
- Fajita spice blend:
- 2 teaspoons chili powder
- 2 teaspoons cumin
- 1.5 teaspoons garlic powder
- 1 teaspoon paprika
- 1 teaspoon onion powder
- 1 teaspoon salt
- 1/2 teaspoon pepper
- For the canned coconut cream, make sure to shake the can a few times prior to opening it to incorporate the solid cream back into the liquid. Depending on the brand used or temperature stored at, the liquid and solid parts can separate
- If adding a can of diced tomatoes, you may need to cook for an extra 5 to 10 minutes to let extra moisture bake off
Keywords: Whole30 casserole, chicken casserole, shredded chicken, low carb casserole, cauliflower rice, paleo, gluten free casserole, chicken fajitas
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