Cheesy Chicken Fajita Casserole

My teenage son actually asked for seconds when I first made this casserole on a chaotic Tuesday night. The kitchen smelled incredible while those peppers caramelized, and I knew I was onto something special when the whole family gathered around the oven watching the cheese bubble up golden and perfect.

Last winter, my neighbor dropped by unexpectedly while this was baking, and she literally stayed for dinner just from following the smell wafting into the hallway. Now she requests it every time I invite her over, and I always double the recipe so there is plenty to share.

Ingredients

• 3 cups cooked chicken breast: Rotisserie chicken works perfectly here and saves so much time on busy weeknights
• 3 bell peppers (red, green, yellow): The different colors make it gorgeous and each brings a slightly different sweetness
• 1 large onion: Slice it thin so it gets those sweet, caramelized edges while cooking
• 2 cups Mexican blend cheese: Do not skip the cheese on top because that crispy golden layer is the best part
• 1/2 cup sour cream and 4 oz cream cheese: These together create the most incredible creamy sauce that binds everything
• 10 oz diced tomatoes with green chilies: Drain them well so your casserole does not get too watery
• Chili powder, cumin, smoked paprika: This trio gives you that authentic fajita flavor without measuring a dozen spices

Instructions

Get your oven ready:

Preheat to 375°F and grease a 9x13 dish really well because that cheese will stick to everything

Caramelize the vegetables:

Heat olive oil in a large skillet and cook those sliced peppers and onions for about 8 minutes until they are soft and starting to brown in spots

Mix everything together:

Combine the chicken, veggies, tomatoes, and all those spices in a big bowl, then stir in the softened cream cheese and sour cream until it is all creamy and coated

Assemble and bake:

Spread the mixture in your prepared dish, cover it completely with that shredded cheese, and bake for about 30 minutes until it is bubbling around the edges and golden on top

Let it rest:

Wait 5 minutes before serving so everything sets up a bit and scoop it out cleanly

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This recipe saved me during a particularly hectic month when I was working late every single day. Knowing I could throw it together in twenty minutes and have something my whole family would actually eat made those exhausting evenings so much more manageable.

Make Ahead Magic

You can assemble the entire casserole up to 24 hours ahead and keep it covered in the refrigerator. Just add about 10 minutes to the baking time since it will be cold when it goes into the oven.

Serving Suggestions

I love setting up a little toppings bar with sour cream, extra salsa, and maybe some sliced avocado or guacamole. Warm flour tortillas on the side turn this into a complete fajita experience that everyone can customize to their liking.

Freezing Instructions

This casserole freezes beautifully either before or after baking. If freezing unbaked, thaw completely in the refrigerator before baking as directed. For already baked portions, wrap individual servings and reheat in the microwave for about 3 minutes.

• Wrap tightly with plastic wrap and foil to prevent freezer burn
• Label with the date and baking instructions
• It will keep well for up to 3 months in the freezer

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There is something so satisfying about watching my family dig into this casserole, all those familiar fajita flavors coming together in such an easy, comforting way. It has become one of those recipes I make on repeat without even thinking about it.

Recipe FAQs

→ Can I make this casserole ahead of time?

Yes, you can assemble the entire casserole up to 24 hours in advance and refrigerate it before baking. When ready to serve, bake as directed, adding an extra 5-10 minutes if baking from cold.

→ What can I serve with this casserole?

Warm tortillas, fluffy rice, or a crisp green salad make excellent sides. You can also serve with guacamole, pico de gallo, or additional sour cream for extra creaminess.

→ Can I use rotisserie chicken?

Absolutely. A store-bought rotisserie chicken works perfectly and saves time on cooking. Simply shred or cube about 3 cups of meat and proceed with the recipe as written.

→ How can I make this spicier?

Add extra cayenne pepper to the seasoning blend, incorporate diced jalapeños with the bell peppers, or use a spicy Mexican cheese blend. You can also drizzle hot sauce over individual servings.

→ Can I freeze this casserole?

Yes, freeze before baking by wrapping the prepared dish tightly in plastic wrap and foil. It will keep for up to 3 months. Thaw overnight in the refrigerator before baking as directed.

→ What other proteins work in this dish?

Shredded turkey, ground beef, or even pulled pork make delicious substitutes. Cooking times remain the same, though ground meat should be browned and drained before adding.