Cheesy Chicken Fajita Casserole

Rainy Tuesdays were made for recipes like this. I had a rotisserie chicken from the grocery store and three bell peppers that needed using, plus two kids who would ask what was for dinner approximately every seven minutes. This casserole came together in that sweet spot between chaos and comfort, and the way my kitchen smelled when it came out of the oven made the entire week feel softer somehow.

My sister was over that first night, skeptical about another casserole experiment, but she went back for seconds and then actually texted me the next morning asking for the recipe. Thats when I knew this one was a keeper.

Ingredients

• 3 cups cooked chicken breast: Rotisserie chicken works beautifully here, or use leftover cooked chicken from another meal
• 3 large bell peppers: The mix of red, green, and yellow creates such beautiful color, but use whatever you have
• 1 large onion: White or yellow both work, sliced into thin strips
• 2 cups shredded Mexican blend cheese: Dont skip this, the cheesy top is what transforms it from dinner to comfort food
• 1/2 cup sour cream: Adds that creamy tang that cuts through the spices
• 4 oz cream cheese: Softened so it incorporates smoothly into the mixture
• 1 can diced tomatoes with green chilies: Drain them well so your casserole doesnt get watery
• 1 tsp chili powder, 1 tsp cumin, 1/2 tsp smoked paprika: This trio creates that classic fajita flavor profile
• 1/2 tsp garlic powder and onion powder: Building layers of flavor without chopping
• 1/4 tsp cayenne pepper: Optional but recommended if you like a little heat
• Salt and black pepper: Dont be shy with seasoning, it makes everything pop
• 1 tbsp olive oil: For sautéing those vegetables until theyre sweet and tender

Instructions

Get your oven ready:

Preheat to 375°F and grease a 9x13-inch dish with butter or cooking spray

Sauté the vegetables:

Heat olive oil in a large skillet over medium-high heat, add sliced peppers and onions, cook for 6 to 8 minutes until theyre soft and starting to caramelize at the edges

Mix everything together:

In a large bowl, combine chicken, cooked vegetables, diced tomatoes with green chilies, all the spices, cream cheese, and sour cream until its all evenly coated

Assemble the casserole:

Spread the mixture in your prepared dish and sprinkle that shredded cheese all over the top

Bake until bubbly:

Cook for 25 to 30 minutes until the cheese is golden and everything is hot throughout

Let it rest and serve:

Wait about 5 minutes before serving, and garnish with fresh cilantro and green onions if you want it to look pretty

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Last Friday, I made this for a dinner with friends and everyone stood around the island eating it straight from the dish with forks. Something about fajita flavors in casserole form just makes people gather closer.

Make Ahead Magic

You can assemble this entire casserole up to 24 hours ahead, cover it tightly, and keep it in the refrigerator until youre ready to bake. Just add about 5 to 10 minutes to the baking time since it will be cold.

Serving Ideas

Warm flour tortillas on the side turn this into a complete meal, but Ive also served it over cilantro lime rice when I want something more substantial. A simple green salad with lime dressing cuts through all that richness.

Leftovers and Storage

This reheats beautifully and somehow tastes even better the next day as the flavors meld together. Store it in an airtight container for up to 4 days.

• Reheat individual portions in the microwave for about 2 minutes
• Cover the whole dish with foil and reheat at 350°F for 15 to 20 minutes
• Freeze unbaked casseroles for up to 3 months, thaw before baking

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Hope this becomes one of those recipes you turn to without thinking, the one that always works.

Recipe FAQs

→ Can I use rotisserie chicken for this casserole?

Yes, rotisserie chicken works perfectly and saves time. Simply shred about 3 cups from a store-bought rotisserie chicken and proceed with the recipe as written.

→ Can I make this casserole ahead of time?

Absolutely. Assemble the entire casserole, cover tightly, and refrigerate for up to 24 hours before baking. You may need to add 5-10 minutes to the baking time if baking from cold.

→ What can I serve with this fajita casserole?

Warm flour or corn tortillas, Spanish rice, refried beans, or a simple green salad all complement this dish well. The casserole is hearty enough to stand alone as a complete meal too.

→ How do I store leftovers?

Store leftover portions in an airtight container in the refrigerator for 3-4 days. Reheat individual servings in the microwave or cover the entire dish with foil and warm in a 350°F oven.

→ Can I freeze this casserole?

Yes, you can freeze the assembled unbaked casserole for up to 3 months. Thaw overnight in the refrigerator before baking. Already-baked portions can also be frozen for 2-3 months.

→ How can I make this spicier?

Add diced jalapeños to the vegetable mix, increase the cayenne pepper to 1/2 teaspoon, or use pepper jack cheese in place of some of the Mexican blend for extra heat.