There’s something magical about the aroma of sizzling onions and peppers mingling with seasoned chicken—it’s the unmistakable scent of fajitas. Now, imagine capturing that same mouthwatering flavor in a warm, cheesy, oven-baked casserole. That’s exactly what you get with this Fajita Chicken Casserole—a hearty, satisfying dish that combines Tex-Mex flair with the ease of a one-dish meal.

Whether you’re hosting a casual family dinner, prepping meals for the week, or craving a comforting dish after a long day, this recipe fits the bill perfectly. Inspired by the bold flavors of traditional fajitas and designed for simplicity, this casserole is a fusion of convenience and taste. It’s a recipe that brings people together, sparks conversation, and delivers smiles at the dinner table.

Why You’ll Love This Fajita Chicken Casserole

This isn’t just another chicken casserole—it’s a celebration of flavors, textures, and colors. Here’s why this dish is going to become a favorite in your kitchen:

✅ Quick and easy to assemble with simple, everyday ingredients
🌶️ Bold Tex-Mex flavors in every bite
🧀 Melted, gooey cheese that adds irresistible richness
🍽️ Perfect for meal prep and reheats beautifully
🥗 Versatile pairing options, from tortilla chips to fresh salads

Plus, it’s a fantastic way to use up leftover chicken or rice. If you’re looking for a fuss-free dinner idea that doesn’t sacrifice flavor, this is it.

Ingredients: Everything You’ll Need

Here’s a list of what you’ll need to bring this casserole to life. All the ingredients are easy to find and likely already in your pantry or fridge.

Main Ingredients:

1 pound chicken breasts, cooked and shredded (rotisserie chicken works great!)
1 packet (1 oz) fajita seasoning mix – gives it that signature Tex-Mex flavor
1 bell pepper, sliced (red, green, yellow, or orange – your choice)
1 onion, sliced
1 cup cooked rice – white or brown rice both work well
1 cup shredded cheddar cheese
1 cup shredded Monterey Jack cheese
1 cup sour cream
1/2 cup salsa – use your favorite jarred or homemade variety
2 tablespoons olive oil – for sautéing the veggies

Optional Toppings:

Chopped fresh cilantro
Extra sour cream
Sliced jalapeños
Diced avocado or guacamole
Fresh lime wedges

Step-by-Step Directions

1. Preheat and Prepare

Start by preheating your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with cooking spray or a drizzle of olive oil. This ensures nothing sticks and clean-up is a breeze.

2. Sauté the Vegetables

In a medium skillet, heat the 2 tablespoons of olive oil over medium heat. Add the sliced bell pepper and onion, cooking until they’re soft and slightly caramelized—about 5 minutes. This step brings out their natural sweetness and enhances the overall depth of flavor.

3. Mix the Filling

In a large mixing bowl, combine:

The shredded chicken
Cooked rice
Fajita seasoning mix
Sour cream
Salsa
The sautéed peppers and onions
Half of the cheddar and Monterey Jack cheeses

Stir everything together until well-mixed. The mixture should be creamy and vibrant, with every ingredient coated in flavorful seasoning.

4. Assemble the Casserole

Transfer the mixture into the prepared baking dish, spreading it out evenly with a spatula or spoon. Sprinkle the remaining cheese on top, creating a golden, gooey topping once baked.

5. Bake to Perfection

Place the casserole in the oven and bake for 20–25 minutes, or until the cheese on top is fully melted and bubbly around the edges. For a golden finish, broil for an additional 2–3 minutes—just keep a close eye on it.

6. Garnish and Serve

Once out of the oven, let the casserole rest for a few minutes. Then, garnish with chopped cilantro or any of your favorite toppings. Serve hot and enjoy the fiesta of flavors!

Serving Suggestions: Complete the Meal

This Fajita Chicken Casserole is fantastic on its own, but it also shines with the right sides and garnishes:

Tasty Pairings:

Tortilla chips for scooping or adding crunch
A simple green salad with lime vinaigrette
Mexican street corn (elote) or roasted corn
A side of black beans or refried beans
Warm flour or corn tortillas

Drink Ideas:

A cold Mexican lager
Fresh lime agua fresca
Margaritas (classic, spicy, or mango!)

This dish also makes a great next-day lunch—just pack up leftovers in an airtight container and reheat in the microwave or oven.

Make-Ahead and Storage Tips

Meal prepping? Hosting a gathering? You’ll be glad to know this casserole is extremely make-ahead friendly.

To Make Ahead:

Assemble the casserole as instructed, but don’t bake.
Cover tightly with foil or plastic wrap and refrigerate for up to 24 hours.
When ready to bake, add 5 extra minutes to the cook time since it’ll be cold from the fridge.

To Freeze:

Assemble the unbaked casserole and wrap it well.
Freeze for up to 3 months.
When baking from frozen, thaw overnight in the refrigerator first, then bake as directed.

Storing Leftovers:

Store cooked leftovers in an airtight container for 3–4 days in the fridge.
Reheat in the microwave or oven until warm throughout.

Customize It: Make It Your Own

One of the best things about this recipe is how customizable it is. Here are some easy variations to suit different dietary needs or flavor preferences:

Low-Carb Version:

Swap rice for cauliflower rice to make it keto or low-carb-friendly.

Add More Veggies:

Throw in some corn, black beans, or zucchini for added nutrition and texture.

Spice It Up:

Use a spicy salsa, or add chili flakes or jalapeños to the mix for extra heat.

Different Proteins:

Substitute chicken with shredded beef, ground turkey, or even tofu for a vegetarian twist.

Dairy-Free:

Use dairy-free sour cream and vegan cheese alternatives for a lactose-free version.

Frequently Asked Questions (FAQ)

Can I use store-bought rotisserie chicken?

Absolutely! Rotisserie chicken is a great time-saver and adds fantastic flavor.

Is this casserole spicy?

It has mild to medium heat, depending on your fajita seasoning and salsa. To control spice, opt for a mild salsa and seasoning blend.

What kind of rice works best?

Long-grain white rice is classic, but brown rice or even quinoa works well too.

Can I double this recipe for a crowd?

Yes! Double the ingredients and use two baking dishes, or one larger casserole dish, if available.