This Chicken Fajita Casserole is a tasty, easy-to-make dish for busy weeknights. The ingredients are simple and flavorful - juicy chicken, peppers, and onions, all bathed in a delicious salsa-y sauce. It's also great for meal prepping so you can't go wrong with this simple recipe.

Jump to:
Why you'll love this recipe
✔️ It's an easy one-pan dinner that can be ready in under an hour.
✔️ Full of flavor and nutrition, with a great mix of veggies, chicken, and cheese.
✔️ The cheese layer adds a delicious richness that takes this dish to the next level. Plus, you can never have too much cheese.
Why this recipe works

Ingredients
Please refer to the printable recipe card at the bottom of this post for the exact measurements.
- chicken breasts
- bell peppers
- red onion
- jalapeno pepper
- Rotel (canned tomatoes with green chilies)
- shredded cheese
- fajita seasoning
- olive oil

Instructions
This is an overview of the instructions. For complete directions, scroll down to the bottom.
- Preheat the oven to 350 degrees. Spray 9x13 casserole dish, set aside.
- Thinly slice the chicken into strips. Place in a large mixing bowl. Sprinkle with olive oil and two tablespoons fajita seasoning.
- Slice the bell peppers, jalapeno and onion into thin strips. Add to the bowl with the chicken. Add remaining olive oil and fajita mix. Mix thoroughly to combine.
- Pour in the Rotel tomatoes, and mix to combine everything. Spoon into the prepared casserole dish.
- Top the dish with shredded cheese. Bake uncovered for 30-35 minutes until the chicken is cooked and the cheese is melty.
- If desired for the last two minutes, place the chicken under the broiler for 2 minutes until the cheese is golden brown.
- Serve with warmed tortillas and your favorite toppings!
Equipment
The following are affiliate links. We participate in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
- 9x13 casserole dish
- knife and cutting board
- large bowl
Don't forget to check out my Amazon storefront for some of my favorite products! 🛍️
FAQ's
Yes, this casserole when baked as directed is low-carb.
No, fajita and taco seasoning are different, although they have similar ingredients. The spice blends are different, so you will want to use fajita seasoning for this recipe.
You will need raw chicken breasts to make this delicious recipe.

Deb's tips
- I like to use freshly shredded cheddar cheese for this easy recipe, but you can use any shredded cheese you have on hand.
- You can use any bell peppers, I like to use a mix of colors, but just green bell peppers will work for this recipe.
- Yellow onion or sweet onion tastes best for cooking, so I tend to use yellow onions when I make fajitas for the best flavor.
- Don't forget to grease your casserole dish well for easy cleanup. You can spray it with nonstick cooking spray or grease it with oil or butter.
- Fresh cilantro, green onions, or even parsley make a great garnish for this dish.
- Serve with flour tortillas or on a bed of tortilla chips if you want to turn this into nachos.
Variations
- If you want to add a little more protein to this casserole you can add in andouille sausage while it bakes for even more flavor.
- Stretch this casserole a little further by adding a can of drained and rinsed black beans or even drained corn.
- Instead of olive oil, you could use any mild flavored oil that you like to cook with, canola oil or even avocado oil will work for this casserole.
- If you want to make this dish low-carb, serve it with low-carb tortillas, or on top of a bed of cauliflower rice for a delicious meal.
Storage
Refrigerate - Leftovers will keep in an airtight container in the refrigerator for up to 3 days.
Freezer - This casserole can be frozen before or after baking, just make sure it is stored properly in an airtight container. It should last up to 3 months if stored correctly.
Reheating - Place leftovers in a microwave-safe dish and reheat until warm. Or place in a preheated oven at 350 degrees for 12 - 15 minutes or so, depending on the amount of leftovers.

Related recipes
- Are you looking for new ideas for easy dinners the whole family will love? If so, check out these Easy Chicken Casserole recipes for a few minutes. There are bound to be a few that your family will enjoy.
- This Taco Spaghetti is my favorite casserole when I crave a creamy, cheesy, and hearty meal. You will love this simple taco-inspired casserole recipe.
- This Mexican Chicken Marinade recipe is a main dish that the entire family will love when you want something healthy, light, and flavorful.
Serve with
- If you ask me, you can't have Mexican food like this chicken fajitas casserole with serving some Easy Guacamole. It's the perfect creamy and flavorful topping for fajitas.
- If you love to make your favorite Mexican restaurant at home like I do, then next time you are going to want to make this Homemade Beef Barbacoa Tacos. It's bursting with flavor, easy to make, and takes just like your favorite restaurant meal.
- This Mexican Tater Tot Casserole is a family favorite in our house. It's a Mexican twist on a classic casserole, you won't regret making this hearty meal for your family.
Hey, if you want to catch all my videos, be sure to subscribe to my YouTube Channel. You'll be notified each time I share a new video!
If you love this recipe, please leave a ⭐⭐⭐⭐⭐ rating!
Chicken Fajita Casserole
Ingredients
- 2 chicken breasts about 1 ¼ pound, you can also use chicken thighs if you prefer. Sliced into thin strips.
- 3 bell peppers I recommend using a rainbow of colors. Sliced into strips.
- 1 red onion thinly sliced
- 1 jalapenos thinly sliced, seeded if desired (optional)
- 10 ounce Rotel (canned tomatoes with green chilies) drained.
- 1 cup shredded cheese
- 3 tablespoons fajita seasoning divided
- 2 tablespoons olive oil
I earn a commission from Instacart from qualifying purchases.
Instructions
- Preheat the oven to 350 degrees. Spray 9x13 casserole dish, set aside.
- Thinly slice the chicken into strips. Place in a large mixing bowl. Sprinkle with olive oil and two tablespoons fajita seasoning.
- Slice the bell peppers, jalapeno and onion into thin strips. Add to the bowl with the chicken. Add remaining olive oil and fajita mix. Mix thoroughly to combine.
- Pour in the Rotel tomatoes, and mix to combine everything. Spoon into the prepared casserole dish.
- Top the dish with shredded cheese. Bake uncovered for 30-35 minutes until the chicken is cooked and the cheese is melty.
- If desired for the last two minutes, place the chicken under the broiler for 2 minutes until the cheese is golden brown.
- Serve with warmed tortillas and your favorite toppings!
Leave a Reply