I created this Fajita Chicken Casserole to bring together the bold flavors of fajitas—tender chicken, bell peppers, onions, and spices—baked in a cheesy, creamy base for a comforting, all-in-one casserole. It’s an easy crowd-pleaser with minimal fuss and maximum flavor.

Why You’ll Love This Recipe

I love how this casserole captures that classic fajita sizzle without having to sear and serve. With seasoned chicken and veggies, gooey cheese, and a rich sauce, it feels like a Tex‑Mex dinner made effortless. It’s perfect for weeknight meals, meal prep, or feeding a hungry group.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

Chicken breast or thighs, cooked and shredded or diced
Bell peppers (a mix of colors), sliced
Onion, sliced
Olive oil or butter
Garlic, minced
Fajita seasoning or homemade spice blend (cumin, chili powder, paprika, garlic powder, salt, pepper)
Cream cheese or sour cream
Shredded cheddar, Monterrey Jack or Mexican blend cheese
Optional: canned diced green chiles or jalapeños
Fresh lime juice and chopped cilantro for finishing

Directions

I preheat the oven to 375 °F (190 °C).
I sauté peppers and onions in oil or butter over medium heat until softened and slightly caramelized. I stir in minced garlic for the final minute.
I add cooked chicken along with fajita seasoning (and green chiles or jalapeños if using), tossing everything to coat and heat through.
I stir in cream cheese or sour cream until it melts into the mixture, creating a creamy sauce.
I transfer the mixture to a greased baking dish, then top with shredded cheese in an even layer.
I bake until the cheese is melted and bubbly, about 15–20 minutes, with an optional broil for 1–2 minutes to brown the top.
Before serving, I squeeze fresh lime juice over the casserole and sprinkle chopped cilantro for brightness.

Servings And Timing

This casserole serves 6 to 8 people as a hearty main dish.

Prep time: 15 minutes (assuming cooked chicken)
Cook/assembly time: about 10 minutes
Bake time: 15–20 minutes
Total time: approximately 40–45 minutes

If I’m starting with raw chicken, I cook and shred it first—adding about 20 minutes for that step.

Variations

I substitute chicken with shredded turkey, steak strips, or seasoned beans for a vegetarian version.
I add black beans or corn to the filling for extra texture and fiber.
I use pepper jack or chipotle cheddar for spice and smoky flavor.
I layer on crushed tortilla chips before baking for crunch, or sprinkle them on top mid-bake.
I drizzle with salsa verde or chipotle mayo after baking for added flair.

Storage/Reheating

I store leftover casserole in an airtight container in the fridge for up to 3 days. I reheat individual servings in the oven at 350 °F until warmed through and the cheese is melty again. I also reheat in a skillet or microwave—adding a splash of water to revive creaminess.

Fajita Chicken Casserole

FAQs

What Cooked Chicken Works Best?

I use shredded rotisserie chicken, grilled chicken breast, or leftover fajita chicken—anything seasoned or pre-cooked helps save time and deepen flavor.

Can I Make This Ahead Of Time?

Yes—I assemble the casserole (uncooked), cover it tightly, and refrigerate up to 24 hours. I bake it straight from the fridge, adding a few extra minutes if needed.

Can I Freeze It?

Absolutely. I freeze cooled casserole (before or after baking) in a freezer-safe dish or wrapped container. I thaw overnight in the fridge and bake or reheat until hot and bubbly.

How Can I Make It Lighter?

I substitute light Greek yogurt for cream cheese or sour cream and use reduced-fat cheese. I also reduce oil and serve with a side salad for a lighter plate.

What Should I Serve With This Casserole?

I love serving it with warm tortillas or tortilla chips, Spanish rice, guacamole, pico de gallo, or a simple green salad to round out the meal.

Conclusion

I love making this Fajita Chicken Casserole when I want all the flavors of fajitas in one easy dish. With seasoned chicken, peppers, creamy sauce, and melty cheese baked to perfection, it’s effortless, satisfying, and great for feeding a crowd.