Cheesy Chicken Fajita Casserole – moist shredded chicken paired with onions and colorful bell peppers cooked down in luscious cream cheese and colby cheese sauce, seasoned with traditional fajita spices and baked until golden and bubbly. Serve it as an entree or a dip.

Chicken Fajita Casserole (Entree or Dip!)
It’s no secret that I love Mexican-inspired dishes. My southwest chicken skillet is in regular rotation as well as crockpot salsa chicken. They’re easy, delicious, and cheesy!
This recipe for a Homemade Cheesy Chicken Fajita Casserole is no different. It’s perfect for game day or any occasion where you need to make something yummy and hearty in the oven! It can serve as an appetizer or a main dish.
Unlike my baked chicken fajitas that need assembling, this take on fajitas is baked in a cheesy casserole form.
Ingredients include shredded chicken, onions, bell peppers, cream cheese, fajita seasoning, and shredded colby. All that is needed are tortilla chips (corn or flour), tortillas (flour or corn), and a serving platter! Or you can scoop it right out of the baking dish with chips!
Why you’ll love this Chicken Fajita Casserole
- All the traditional flavors of chicken fajitas in a cheesy casserole form.
- So easy to make – just dump everything into one dish and bake!
- It can be made ahead of time, so you don’t have to worry about it on game day or party day.
- Versatile – enjoy with tortilla chips, flour tortillas, corn tortillas, veggie sticks, pita chips, or crackers.
- The perfect dish for when you’re craving Mexican flavors.

Equipment needed to make this Fajita Casserole Recipe
- Large Skillet
- Veggie Chopper – this is my new favorite kitchen tool. It quickly & evenly will chop your onions and bell peppers.
- Silicone Spatulas
- Box Grater – for shredding your cheese.
Ingredients you’ll need to make Homemade Chicken Fajita Dip
Below is a list of the ingredients you’ll need to gather to make this recipe, why you need them, and possible substitutions. Scroll all the way down for the full recipe card with measurements.
- Chicken – You’ll need 1-2 cups of cooked chicken. Either shred a rotisserie chicken (for ease) or make instant pot shredded chicken from breasts or thighs (also easy!)
- Bell Peppers – Any combo of colors you like – I used red/orange/yellow. Green tend to be the most bitter while orange and yellow are sweeter, and red being the sweetest.
- Onion – White onion to dice.
- Seasonings – Salt and fajita seasoning. If you’d like to make your own fajita seasoning, I have the mix below.
- Cheese – You’ll need a mix of shredded cheese and room temperature cubed cream cheese. Colby works well, as does cheddar. I recommend shredding it yourself off a block for the best results. Pre-shredded cheese is convenient but it has anti-caking agents on it that prevents it from melting nicely.

How to make Baked Chicken Fajita Casserole In The Oven
- STEP ONE: First, saute the diced onion and peppers in olive oil over medium high heat in a large skillet for 4-5 minutes or until tender.

- STEP TWO: Next, turn the heat to low and add the diced (or shredded) chicken, cubed cream cheese, fajita seasoning and half of the shredded cheese. Heat until melted, stirring often.
- STEP THREE: Finally, pour the mixture into a greased casserole dish (shown is a 6″ x 8″), top with remaining cheese, and bake for 25-30 minutes at 350° until melted and bubbly.


Slow Cooker Instructions
This dish can easily be made in the slow cooker!
Prep all ingredients and add them to the basin of a 6 quart slow cooker, reserving 1/2 cup of shredded cheese.
Cover and turn on HIGH for 1-2 hours or LOW for 2-3 hours, stirring occasionally, if possible.
30 minutes before you’re ready to serve, sprinkle the remaining cheese over the top, replace the lid, and let it melt.
Enjoy!
How to serve Chicken Fajita Casserole
If you’re serving this casserole as a dip, it will pair well with my taco dip and homemade tortilla chips (made in the oven or air fryer)!
If you’re serving it as a main dish, you can pair it with my green chile corn casserole and a quick 60-second chocolate chip cookie. It’s the perfect complete dinner!
Another option is to spread some between two tortillas and make a chicken fajita quesadilla or roll-up!
How To Store & Reheat Leftovers
You’ll want to store any leftover casserole in an airtight container in the fridge. It will last for up to four days.
To reheat, place it in a baking dish cover with foil, and bake at 350 degrees until heated through. You can also microwave it on medium power for about two minutes or until warmed through.

Cheesy Chicken Fajita Casserole FAQs
Can I use chicken thighs in this recipe?
Yes! You can use chicken thighs in this recipe. Keep in mind that chicken thighs are fattier and may overwhelm your dip with an oiliness. I prefer chicken breasts but it’s up to you.
What If I don’t have pre-made fajita seasoning?
You can make your own fajita seasoning by mixing together:
- 2 teaspoon chili powder
- 1 teaspoon ground cumin
- 1 teaspoon smoked paprika
- 1/2 teaspoon garlic powder
- 1/2 teaspoon onion powder
- cayenne pepper to taste
- 1/4 teaspoon salt
Can I make this recipe ahead of time?
Yes! This recipe can be made ahead of time. Simply follow the instructions up until baking and cover with aluminum foil. Store covered in the fridge for up to 24 hours before baking.
If you are making this recipe ahead of time, then I recommend adding at least 15 minutes to your bake time because it will be cold when going into the oven and you want to make sure it is warmed through.
What can I use in place of colby cheese?
If you don’t have colby cheese, then you can use a mild cheddar, or even Monterey jack, pepper jack, or a mix.
What can I serve this fajita dip with other than tortillas?
This chicken fajita dip would make a great filling inside of an omelet for a hearty breakfast. It would also be great stuffed inside of jalapeños and baked in the oven for a fun appetizer!
You can also serve it with cilantro lime rice and beans and eat it as a main course.
Need more casserole recipes? Try these:
Baked Salsa Chicken Casserole
Cheesy Chicken Broccoli and Rice Casserole
Spinach Artichoke Chicken Casserole
Click here for my entire collection of casserole recipes.
Need more hot dip recipes? Try these:
Slow Cooker Buffalo Chicken Dip
Crock pot Spinach Artichoke Dip
Rotel Dip with Ground Beef
Click here for my entire collection of dip recipes.

It is super delicious!! So easy to make
Thank you!
This sounds like a winner for my rotation at evening dinner. Can ground beef be substituted for the chicken? If anyone has tried this please post your ideas/comments
Thanks Melissa for some great recipes.
Hi Gwenda! I think ground beef sounds good. I would brown the meat (I prefer sirloin/a lean cut) and drain any excess grease, then follow the recipe are written 🙂
You say use a small, casserole dish! Can you be specific in what kind, exactly? 9×13? 8×8? 9×9?
Shown is a 6 x 8 baking dish. 8 x 8 will be fine.
I used a 9×9 to be safe and I was.
Plus it’s the easiest dish to clean!😝
The recipe does not contain how much of each ingredient. The ingredients sounds great but without the measurements of the ingredients, could make the difference between a good recipe and a bad recipe.
Hi Roger, I agree measurements are critical. You actually scrolled past the recipe card to leave this comment 🙂 Click here to go back up to it.
This is so incredibly delicious!!!
Made it for dip with scoop chips the first night and made actual fajitas the 2nd night, with sour cream and salsa. OMG!!! Tonight trying it on burgers!
The possibilities are endless for this dish!
Thank you, Jack!
This recipe is a new family favorite!!!!
It is delicious and full of flavor. Plus it is so easy to put together.
I have made it as written and then I substituted ground beef instead of the chicken, both ways are fantastic!
Thank you Melissa!!!
You’re welcome! Thanks for reporting back, I’ll have to try with ground beef.