Chicken Fajita Casserole
Fajita chicken, onions, and peppers baked in a creamy cheese sauce? This Chicken Fajita Casserole Recipe may be my favorite casserole yet. It is perfect for busy weeknights with a dollop of sour cream and avocado on top and paired with a fresh green salad.
I love Mexican food. Since most of my kids love Mexican food too, we add it into the dinner rotation at least a few times a month.
Most of the time, we just have this freezer friendly taco meat (which I do meal prep), but this chicken fajita bake is a welcome step up from a typical Taco Tuesday. Once you try my low carb keto fajita chicken casserole, I guarantee the juicy chicken and melty cheese will make you want to make it again and again. It’s an easy dinner that is quick enough that even if it’s 5 pm, you can make it!
If you are here because you love Mexican food, make sure to try my Keto Taco Salad Casserole Recipe and Keto Chicken Tortilla Soup.
Ingredients
- Chicken Thighs – I prefer using boneless chicken thighs in this recipe but chicken breasts work too. You can also swap in cooked, shredded rotisserie chicken.
- Yellow Onion – Any variety of onions are fine.
- Red Bell Peppers – Sweet bell peppers are the best choice for fajitas.
- Cream Cheese – Adding cream cheese makes a delicious creamy sauce. It’s definitely not traditional but it is SO good. Trust me on this.
- Fajita Seasoning – It is so easy to make your own! Click to learn to make my homemade fajita seasoning: Keto Fajita Seasoning. It uses cumin, paprika, garlic powder, onion powder, chili powder, etc. It is mild enough for the whole family.
- Shredded Cheese – Shredded cheddar cheese, Monterey Jack, or a Mexican blend are all good choices. For a spicier version, try adding Pepper Jack cheese.
See quantities in the recipe card.
How to Make a Chicken Fajita Casserole
Step One: Pop the chicken into the oven to bake in the baking dish or casserole dish you will use for the casserole.
Step Two: While the chicken is baking saute the veggies.
Top Tip💡
Cooking the vegetables in a skillet helps give this casserole a true fajita flavor. Adding raw vegetables and baking does not yield the same result. If you’d like to make this entirely on the oven you can roast the onions and peppers on a baking sheet instead of pan-frying them.
Step Three: Shred the chicken. Then combine the hot shredded chicken with the fajita veggies, cream cheese, and seasonings in a large bowl.
Note: Boneless skinless chicken thighs shred easily but if you choose to use boneless skinless chicken breasts instead it may be easier to just chop them.
Step Four: Put the fajita chicken mixture in the casserole dish, top with cheese, and bake until bubbly and golden. Serve this easy chicken fajita casserole with a salad or your favorite fajita toppings!
Storage
Store leftovers in an airtight container in the fridge for 4-5 days.
Variations
Dairy-Free – Cutting back on dairy and still want fajitas? Try these Baked Chicken Fajitas instead.
Spicy – Sauté some jalapeno peppers along with the peppers and onions. For milder heat, remove the seeds from the jalapenos. Canned green chilies work too.
Chipotle – Add some smokiness with chipotle puree. Simply blend up a can of chipotles in adobo and add a bit to taste to the cooked chicken mix before its added to the casserole pan.
Cast Iron Skillet – Cook the chicken in the pan, remove, cook the peppers and onions, add all of those to a large bowl, add the other ingredients, and mix. Put back into the skillet and bake until hot and bubbly.
Seasoning – To change it up, try my Chicken Taco Seasoning instead of fajita seasoning.
Common Questions
What is Fajita Seasoning?
A blend of spices commonly used for fajitas. I make both my own Homemade Taco Seasoning and Keto Fajita Seasoning. They are quick, easy, and CHEAP!
Can I use chicken breasts?
Yes! Just bake the onions and peppers for 10 minutes before adding strips of raw chicken breasts or they can dry out.
What do I serve with a fajita casserole?
I normally have this on top of cauliflower rice with a green salad on the side. My kids like to add white rice or brown rice, black beans, and tortilla chips. You will definitely want to serve it with traditional toppings like pico de gallo or salsa, sour cream, and guacamole.
Want to Save This Recipe?
Enter your email below & we’ll send it to your inbox. Plus get great new recipes from us every week!
By submitting this form, you consent to receive emails from Joy Filled Eats
Video
Chicken Fajita Casserole
Ingredients
- 10 boneless skinless chicken thighs (about 2 pounds)
- 1 red pepper seeded and sliced into small strips
- 1 large onion peeled and sliced into small strips
- 8 oz cream cheese softened
- 8 oz shredded cheddar
- 1.5 tbsp fajita seasoning
- salt & pepper (optional)
Instructions
- Preheat oven to 350. Put the chicken in the casserole dish you will be using for this dish. Cover with foil and bake until cooked to 160 degrees, about 30-35 min. Cool for a few minutes and then shred or chop into bite-sized pieces. Drain any cooking liquid from the casserole dish.
- Meanwhile, in a frying pan coated with cooking spray, cook the pepper and onion over medium-low heat until they are golden and soft. I let mine caramelize the entire time the chicken was in the oven. I just left the heat between low and medium and popped into the kitchen to give them a stir every 5-10 min. Cool until warm.
- In a large bowl mix the cream cheese, half of the shredded cheddar, and the fajita seasoning. Add the chopped chicken and cooked onion and pepper. Put back into the same casserole dish you cooked the chicken in. Sprinkle on the remaining cheese.
- Bake at 350 for 25-30 min until hot and bubbly.
Notes
Nutrition
Originally Published April 14, 2016. Revised and Republished October 13, 2025.
Can you use chicken breasts instead of thighs?
Yes
Yes just had this with chicken breasts tonight. we prefer breast over thighs as the thighs were greasier meat. I add a whole envelope of fajita seasoning mix as we like it spicier!
I did and it is even better! Added more seasoning mix too. Thighs were too greasy for us with two people with high cholesteral.
Has anyone tried heating this recipe in a crock pot?
Yes, I put everything in but the cream cheese on low for 4-6 hours. I added cream cheese during the last hour then cheddar the last 30 minutes!
Does this freeze well.
I’ve never frozen this casserole. My others freeze well. Lmk if you try to freeze this one how it turns out.
I froze it recently, i left off the cheese on top but it froze very well!
I’ve been meaning to tap out a quick reply since April, but life has been busy!!!
This recipe has become a family favorite!!! It can be tough pleasing 2 adults and 2 girls (ages 10 & 15).
My initial question was about the chicken. That first batch, I went with 1 2 lb. package. It was just easier then breaking up the other package. Everyone ate it and complimented it. I thought the chicken was a little sparse. After playing with it few times, I generally look for a chicken thigh package that is 2½-3 lbs. I pretty much ignore the count, but it’s usually 7-8. We must grow chickens bigger in Texas 😉
I also throw in a 10 oz package of riced cauliflower or broccoli (freezer section) microwaved to package directions, and drained. I like to sneak extra veggies where my daughters won’t notice, and you can’t even taste it 😉
Thanks!
Jim
You can definitely use more chicken. I made a double batch the other day for us and for friends and I ended up putting about the 2 pounds in our casserole and closer to 3.5 in theirs.
Sounds delicious. Since the chicken and veggies are cooked earlier, why would it need so long in the second bake time? Shouldn’t 15 to 20 minutes be enough?
It might be. You just want everything to get hot. In my recipe testing that was closer to 30 minutes.
Going to make this, this weekend. Looks wonderful!
Just wanted to verify proportions — I have 2 packages of boneless chicken thighs in freezer. Counting through package, it looks like there is 11 (5 in 1, 6 in other). Both packages are each 2 lbs. You list 10 thighs, about 2 lbs.
Do I only need 1 package?
Thanks!
Great blog!
Hi Jim, starting with frozen thighs I’d probably begin with 2.5-3 pounds. They release a lot of liquid when cooking. If it seems like too much chicken after they cook you could save some for another use.
This was the bomb,my hubby loves it, I used vegan cream cheese, and Colby cheese, and mini sweet peppers, and some extra seasonings to the chicken for the first bake, turned out delicious.
This was delicious! I used chicken breast and cooked in the Instant Pot first with fajita seasoning for easy shredding. I also use 2 red peppers and one green. Was a big hit with the hubby too! Will be adding this to our meal rotation!
Just made this for dinner tonight. Was a big hit! I used chicken breasts instead of thighs (like them better) and it worked great.
Thanks so much!!! 🙂
If I were to omit the cream cheese, would this be dry? If so what could I use besides that?
You would need to add another liquid. Cottage cheese, salsa, sour cream could all work.
Do you think you could freeze this?
Yes. I’ve had readers freeze this after baking it. I think you could freeze it before baking as well.
YAll so what I did was, in the morning I mixed my chicken/peppers/fajita sauce together in a crock pot and cooked it on low all day and then At dinner time i just broke up the chicken, mixed the cream cheese and shredded Mexican blend cheese, and it came out so so good! And sooooo easy!
Thank you, Melanie! That’s what I was wondering about. Going to do that too!
Is an instant pot the same as a pressure cooker
Yes, an instant pot is an electric pressure cooker.
I absolutely love fajitas. This looks amazing. I never would’ve thought to make a casserole out of them, though. Thank you for sharing this!
What would you say the serving size would be?
A serving is 1/8th of the recipe. I normally just eye it up.
Are the nitrition facts for each servin or for the whole casserole?
For one serving.