This Keto Chicken Fajita Casserole has all of your favorite fajita flavors all in one skillet. Perfect for dinner on busy weeknights!!!
This Keto Chicken Fajita Casserole has all of your favorite fajita flavors all in one skillet. We love this recipe for easy weeknight dinners and the leftovers are even more delicious. With all the toppings like salsa, guacamole, sour cream, and fresh sliced jalapeños you just can't go wrong.
How to make Keto Chicken Fajita Casserole
In just 4 easy steps you'll have a bubbling skillet full of fajita goodness ready in just about 30 minutes.
- You'll start by preheating the oven to 450° F - this will help to get the cheese topping nice and bubbly after cooking the fajitas on the stovetop.
- Heat the butter in a large cast-iron skillet. Add the chicken to the pan and brown 3-4 minutes per side. Add in the peppers and onions along with the taco seasoning. Cook 4-5 minutes until starting to soften.
- Stir in the tomatoes, top with cheese and transfer to the oven. Bake for 10-15 minutes until the top is bubbly.
- Top with desired toppings and serve.
How easy is that?! You also just need a handful of ingredients. We're using chicken strips so you can skip the step of cutting the chicken yourself.
For the fajita seasoning, we recommend our Homemade Taco Seasoning mix. You could also buy the bell peppers and onions already cut if your grocer has a fajita blend in the produce section.
To top it all off you'll cover the fajitas in cheese (we used a Colby Jack cheese blend) and pop it into the oven until the cheese is melted.


Topping options:
We've used the following toppings:
- sour cream
- pico de gallo
- guacamole
- sliced jalapeños
- cilantro
Feel free to use all or only a few of them. In my opinion, the toppings are the best part.
What is the nutritional information for this recipe?
As always, you can find the full nutritional breakdown including the carb count (total carbs and net carbs) for keto at the bottom of the recipe card as well as the servings at the top of the recipe card. You should always double-check your specific ingredients as different brand's ingredients may have different values.

📖 Recipe

Keto Chicken Fajita Casserole
Ingredients
- 3 tablespoons unsalted butter
- 1 lb chicken breast strips
- 1 medium onion thinly sliced
- ½ green bell pepper thinly sliced
- ½ red bell pepper thinly sliced
- 1 jalapeno thinly sliced
- 1 tablespoon taco seasoning
- 1 (14.5-ounce) can fire roasted tomatoes, drained
- 2 cups Mexican blend cheese
Toppings:
- ¼ cup guacamole
- ¼ cup pico de gallo
- ¼ cup sour cream
- 1 Jalapeño thinly sliced
- 1 tablespoon minced cilantro
Instructions
- Preheat oven to 450° F
- Heat the butter in a large cast iron skillet. Add the chicken to the pan and brown 3-4 minutes per side. Add in the peppers and onions along with the taco seasoning. Cooke 4-5 minutes until starting to soften.
- Stir in the tomatoes, top with cheese and transfer to the oven. Bake for 10-15 minutes until the top is bubbly.
- Top with desired toppings and serve.
Gerrie says
Looks fabulous! Partner does not eat chicken....what steak would I choose to make this with beef please? So glad I found you!
Alex Lester says
I would use thinly sliced sirloin or flank steak!
Cathy Barker says
This looks amazing! Does the nutritional information include the toppings?
Cast Iron Keto says
Yes, it does include the toppings!