Can I use fresh spinach instead of frozen?

Absolutely! Just sauté a big handful (it cooks down dramatically) with the other vegetables until wilted, then proceed with the recipe as written.

Can I substitute the condensed soup?

If you’re avoiding processed soups, a quick homemade white sauce (butter, flour, broth, and milk) with a handful of sautéed mushrooms works beautifully. It just takes a few extra minutes.

Can I make it dairy-free?

Yes! Use a plant-based butter, swap in your favorite non-dairy sour cream and use a dairy-free condensed soup or make your own creamy sauce with cashew cream or oat milk.

How do I tell if the chicken is fully cooked?

To check for doneness, make sure the chicken pieces are no longer pink in the middle and juices run clear, or use a thermometer—165°F is the magic number.

Creamy Chicken and Veggie Casserole Recipe

Dinners that check all the boxes—delicious, easy, and good for you—aren’t nearly as rare as you might think. This Creamy Chicken and Veggie Casserole proves it! Imagine juicy chunks of chicken tucked into a medley of colorful veggies, all brought together by the indulgent creaminess of mushroom soup and sour cream. It’s comfort food made simple—just one pan and one casserole dish, minimal prep, and dinner is bubbling away in the oven while you relax or tackle your evening checklist. Perfect for busy weeknights or those times you want cozy flavors without working overtime, this is a dish as rewarding to make as it is to eat!

Why You’ll Love This Recipe

Super Convenient: Minimal chopping, easy steps, and a single casserole dish mean fewer dishes and less stress at dinnertime.
Hearty & Satisfying: The creamy, savory base pairs wonderfully with juicy chicken and veggies—seriously comforting!
Flexible Ingredients: Feel free to use up whatever’s in your fridge; this casserole is a champion for adaptation.
Meal Prep Hero: Leftovers taste even better the next day, so make a big batch and enjoy stress-free lunches.

Ingredients You’ll Need

Here’s a quick rundown of what goes into this flavorful casserole, plus why each element shines:

Chicken breast – Adds lean protein; chopping into bite-sized pieces helps it cook quickly and evenly.
Yellow onion – For sweetness and depth; softens and blends beautifully in the casserole.
Red bell pepper – Provides color and a sweet, crisp bite.
Green bell pepper – Brings a subtly grassy flavor and visual pop.
Frozen spinach – Makes things easy; just squeeze out as much moisture as possible to avoid extra liquid.
Cremini mushrooms – Earthy and meaty, they amp up the umami comfort factor.
Condensed cream of mushroom soup – The shortcut to creamy, savory goodness (use fat-free for a lighter take).
Non-fat sour cream – Adds velvety tang and creaminess, balancing out the soup.
Unsalted butter – For sautéing and richer flavor without going overboard.
Minced garlic – Gives a boost of aromatic “wow.”
Paprika – Slight smoky depth and gentle warmth; don’t skip it!
Salt and pepper – For seasoning to taste.
Tip: Don’t hesitate to swap in pre-cooked rotisserie or leftover chicken if you’re really short on time.

Note: You’ll find the complete list of ingredients, along with their exact measurements, in the printable recipe card at the bottom of this post.

Variations

Craving a twist, or working with what’s on hand? Here’s how to make it your own:

Protein Swap: Try cooked turkey, shredded rotisserie chicken, or even tofu for a meatless version.
Veggie Variety: Use any mix you love—zucchini, broccoli florets, or peas can be added or swapped in.
Cheesy Finish: Sprinkle shredded mozzarella, cheddar, or parmesan over the top before baking for a golden, bubbly crust.
Kick of Heat: Add red pepper flakes or a sprinkle of cayenne if you like things spicy.

How to Make Creamy Chicken and Veggie Casserole

Step 1: Prep

Preheat your oven to 375°F. Chop all your veggies and the chicken into bite-size pieces. Defrost the frozen spinach in hot water right in its packaging, then squeeze out every drop of water—you want flavor, not sogginess!

Step 2: Sauté the Veggies

In a large pan over medium heat, melt the butter. Toss in the garlic, onion, and both bell peppers. Stir and cook until everything softens (onions should look translucent and inviting). Next, add the sliced cremini mushrooms, and continue to sauté until the mushrooms lose most of their moisture and start to brown slightly. Finally, mix in the well-drained spinach.

Step 3: Mix in Creaminess

Once the veggie mixture is ready, stir in the condensed cream of mushroom soup, sour cream, paprika, plus salt and pepper to your liking. This should transform things into a luscious, creamy base.

Step 4: Add Chicken

Mix the raw chicken pieces right in. If you’d rather, lay whole cutlets neatly on top instead (they’ll cook through in the oven).

Step 5: Bake

Spray a large baking dish with nonstick spray. Spread the creamy chicken and veggie mixture into it. Slide the casserole into your hot oven and bake for about 20 minutes, until the chicken is thoroughly cooked and the sauce is bubbling at the edges.

Step 6: Serve!

Let it cool for a few minutes (the aroma will seriously tempt you), then serve up generous scoops. This casserole is fabulous on its own or as the star on top of rice, noodles, or even cauliflower rice.

Pro Tips for Making the Recipe

Drain that Spinach: Get as much moisture out as you can—the secret to avoiding watery casserole.
Don’t Overcrowd the Pan: Sauté veggies in batches if your pan is small; caramelization means better flavor.
Pre-Cook for Peace of Mind: Worried about chicken doneness? Sear it quickly before mixing it into the casserole for extra color and flavor.
Customize the Cream: Want a tangier flavor? Add a dollop of Greek yogurt with the sour cream.

How to Serve

This casserole is downright delicious on its own, but it also serves as a chameleon for your side dish cravings:

Over your favorite starch: Pile on fluffy white rice, nutty brown rice, wide egg noodles, or zoodles for extra veggies.
With a fresh salad: A crisp green salad with lemony vinaigrette is a lovely, light contrast.
With bread: Warm crusty bread makes a perfect vehicle for soaking up every bit of creamy sauce.

Make Ahead and Storage

Storing Leftovers

Let leftovers cool completely, then store them in an airtight container in the fridge for up to 3 days. The flavors get even deeper as they mingle overnight.

Freezing

This casserole freezes wonderfully! Transfer cooled servings into individual airtight containers and freeze for up to 2 months.

Reheating

When ready to enjoy again, microwave individual portions until piping hot, or cover with foil and reheat in a 350°F oven until warmed through. Add a splash of milk or broth if it looks a little thick.

FAQs

Can I use fresh spinach instead of frozen?

Absolutely! Just sauté a big handful (it cooks down dramatically) with the other vegetables until wilted, then proceed with the recipe as written.
Can I substitute the condensed soup?

If you’re avoiding processed soups, a quick homemade white sauce (butter, flour, broth, and milk) with a handful of sautéed mushrooms works beautifully. It just takes a few extra minutes.
Can I make it dairy-free?

Yes! Use a plant-based butter, swap in your favorite non-dairy sour cream and use a dairy-free condensed soup or make your own creamy sauce with cashew cream or oat milk.
How do I tell if the chicken is fully cooked?

To check for doneness, make sure the chicken pieces are no longer pink in the middle and juices run clear, or use a thermometer—165°F is the magic number.

Final Thoughts

Creamy Chicken and Veggie Casserole isn’t just dinner, it’s a kitchen hug on even your busiest nights. Fast to prep, packed with flavor, and endlessly customizable, it’s the ultimate family meal—or meal prep treat—waiting for you to make it your own. Try it this week, experiment with your favorite veggies, and see just how simple homemade comfort can be!