This Chicken Zucchini Casserole is the perfect way to enjoy your summer squash harvest. It’s a low carb dinner that’s both keto-friendly and high in protein, replacing heavy pasta with tender zucchini noodle sheets. Layered with shredded chicken and a zesty homemade sauce, it’s a healthy, gluten-free bake the whole family will love.

Chicken zucchini casserole in a baking dish garnished with parsley.

Why You’ll Love This Recipe

I make this chicken zucchini casserole during July and August months when I have garden fresh zucchini. It’s a chicken and zucchini recipe that is light yet incredibly satisfying – perfect for when you want a “set it and forget it” gluten-free chicken bake that feels like a treat but is actually packed with nutrition.

Here is why it’s a permanent part of our dinner rotation:

  • Easy low-carb dinner: By swapping traditional pasta for zucchini “noodle” sheets, you get one of those rare low carb dinner recipes that actually keeps you full.
  • High in protein: Each serving contains 21g of protein.
  • Garden fresh: It’s the ultimate way to use up an abundance of summer squash or garden zucchini. If you have extra, check out my favorite summer squash recipes for more inspiration!
  • Family approved: Even with the “veggies-forward” approach, the cheesy Mexican-inspired flavors and shredded chicken make it a hit with kids and “hungry boys” alike.
  • Meal prep king: This chicken and zucchini casserole recipe will taste even better the next day as the flavors meld, making it an excellent option for healthy lunches throughout the week.

Ingredients for Zucchini Chicken Casserole

Chicken breasts, zucchini, tomato sauce, quinoa, cheese, jalapeno, maple syrup, garlic powder, taco seasoning, cumin, salt, pepper.
  • Zucchini: You can use green zucchini or yellow summer squash. I used small to medium zucchini. If you have giant garden zucchini, simply slice them into thin rounds.
  • Chicken: This recipe is flexible! Use cooked chicken thighs, boneless skinless chicken breasts, or even ground chicken. It’s a great way to use up leftovers.
  • Tomato sauce: Use a regular, plain tomato sauce. I recommend low-sodium to keep the dish healthy. We add a touch of maple syrup to offset its acidity.
  • Cheese: Tex Mex, Colby, or any good melting cheese works perfectly. Some readers have used mozzarella cheese, although I think it doesn’t add as much flavor.
  • Simple spices: A blend of cumin, garlic powder, jalapeno, taco seasoning and black pepper gives it that zesty flavor. Salt is used for salting zucchini and sauce.
  • Quinoa: We sprinkle a little uncooked quinoa at the bottom of the dish. This is my secret trick to absorb the extra moisture that zucchini naturally releases during baking.

How to Make Chicken Zucchini Casserole

It may look like a lot of steps, but time flies by when making this high-protein Mexican chicken zucchini lasagna!

Preparing chicken, zucchini and sauce for chicken zucchini casserole.
  1. Salt the zucchini: In 9×13-inch baking dish, place sliced zucchini in a single layer and sprinkle with salt, repeating with remaining zucchini. Set aside for 30 minutes. Pro-tip: This step is crucial because it pulls away excess moisture, preventing a watery casserole.
  2. Cook and shred the chicken: Sprinkle your chicken with taco seasoning. In a large skillet over medium heat, cook for about 5 minutes per side until white edges appear and the chicken is cooked through. Transfer to a cutting board and shred with two forks.
  3. Make the homemade sauce: In a large bowl, add tomato sauce, taco seasoning, jalapeno, cumin, garlic powder, salt and pepper; stir to combine and set aside. This zesty sauce is what gives the bake its bold flavor.
  4. Pat dry and assemble: Preheat oven to 375 degrees F. Pat each zucchini layer dry with paper towels. Wipe the baking dish dry, spread a few tablespoons of the sauce on the bottom, and sprinkle with quinoa (my secret for absorbing extra juices!).
Step by step process how to layer chicken zucchini casserole.
  1. Layer: Place sliced zucchini overlapping a bit to create a single layer. Top with 1/3 of shredded chicken, then a bit of cheese (reserving a bit more than half for the top) and 1/3 of the sauce. Continue until you run out of ingredients, finishing with a final layer of zucchini, sauce, and the remaining cheese.
Final chicken zucchini casserole dish.
  1. Bake: Bake covered with aluminum foil for 30 minutes, then uncover and bake for another 20 minutes.

Let stand for 20 minutes before slicing. This allows the layers to set so you get a perfect slice of this gluten-free chicken bake. Cut into 8 slices and serve hot.

Tips for Best Results

  • Use any summer squash: This is one of those versatile summer squash recipes where you can use green zucchini, yellow squash, or a mix of both. “Eating the rainbow” makes the dish look beautiful!
  • Uniform zucchini noodles: For even baking, use a mandoline or grater with slicing blade to get consistent 1/8-inch thickness. I highly recommend wearing cut-resistant gloves for safety.
  • The quinoa trick: Don’t skip the uncooked quinoa! It’s the secret to keeping this high protein bake from getting watery by absorbing the zucchini juices as it cooks. (Breadcrumbs work too, but quinoa keeps it gluten-free).
  • Leftover friendly: This recipe is perfect for using up leftover chicken. I often use my grilled chicken recipe or Instant Pot chicken breast to save time on busy weeknights.
Slice of chicken zucchini casserole on a spatula.

Serving Suggestions

This chicken zucchini casserole recipe is a satisfying low carb dinner all on its own. However, if you are feeding a crowd (or live with 3 hungry boys like I do!), here are some healthy ways to scoop up every last drop of that zesty sauce:

  • Crusty bread: For the ultimate high-protein experience, serve a slice of my Greek yogurt bread or cottage cheese bread on the side. It’s perfect for dipping into the zucchini and sauce!
  • Whole grains: Serve over brown rice or extra quinoa to keep it a high protein and fiber-rich meal.
  • Pasta: Choose a tubular pasta like penne or fusilli. Unlike white pasta, whole grain or legume-based pastas (like chickpea or lentil) are great for soaking up the juices while keeping it a gluten-free chicken bake.
  • Potatoes: For a classic comfort meal, serve this veggie-and-meat bake over creamy mashed potatoes. I always do with baked chicken and peppers, the sauce makes the best “gravy”.

Make Ahead and Storage

Make ahead: You can assemble this casserole up to 24 hours in advance. Simply build the layers, cover the dish tightly with plastic wrap or foil, and refrigerate. Since the chicken is already cooked, it is perfectly safe to prep ahead and bake when you’re ready!

Storing leftovers: Leftovers keep beautifully in the fridge for up to 5 days. Much like borscht, the flavors actually meld and improve the next day. I always recommend using a glass airtight container to keep the zucchini fresh and the sauce zesty.

Reheating: Reheat individual slices in the microwave or place the baking dish back in the oven at 350F until warmed through.

Can You Freeze This Casserole?

The short answer is no. Because zucchini is roughly 90% water, it does not hold its texture well after freezing and thawing. If you place it in the freezer, the zucchini “noodles” will release all their moisture, leaving you with a watery mess rather than a structured casserole.

Recipe Tip

While you shouldn’t freeze the finished dish, you can freeze shredded zucchini in portions! It’s perfect for making healthy zucchini bread during the winter months.

More Healthy Zucchini Recipes to Try

Chicken zucchini casserole garnished with parsley in baking dish.
Chicken zucchini casserole in baking dish.
4.96 from 50 votes

Chicken Zucchini Casserole

This healthy Chicken Zucchini Casserole features layers of shredded chicken, zucchini noodles, and a zesty homemade sauce. A low-carb, high-protein dinner!
Prep: 25 minutes
Cook: 50 minutes
Resting Time: 20 minutes
Total: 1 hour 35 minutes
Servings: 8 servings

Ingredients 

  • 2 pounds zucchini, cut lengthwise into 1/8″ thick slices
  • 1 pound chicken thighs or breasts, boneless & skinless
  • 28 ounces tomato sauce, low sodium
  • 3 teaspoons taco seasoning, low sodium, divided
  • 1 tablespoon jalapeno, minced
  • 2 teaspoons maple syrup or honey
  • 1 teaspoon cumin, ground
  • 1 teaspoon garlic powder
  • 1/4 teaspoon salt, + more for zucchini
  • 1/4 teaspoon ground black pepper
  • 1 teaspoon oil, for frying
  • 1/4 cup quinoa, uncooked
  • 1 1/2 cups Tex Mex , cheddar or Colby Jack cheese, shredded (7 ounces)

Instructions 

  • In 9 x 13 baking dish, place sliced zucchini in a single layer and sprinkle with salt, repeating with remaining zucchini. Set aside for 30 minutes.
  • Sprinkle chicken with 1 tsp taco seasoning and using tongs toss to coat.
  • Preheat large skillet on medium heat, swirl oil to coat and add chicken. Cook for 5 minutes or until white edges appear, turn and cook for 5 more minutes or until cooked through. Transfer to a cutting board and shred with 2 forks. Set aside.
  • In a medium bowl, add tomato sauce, 2 tsp taco seasoning, jalapeno, maple syrup, cumin, garlic powder, salt and pepper; stir to combine and set aside.
  • Preheat oven to 375 degrees F. Pat dry each zucchini layer with paper towels transferring to another dish (plate). You want to absorb moisture between each zucchini layer as much as possible.
  • Wipe dry the baking dish, spread a few tablespoons of tomato sauce mixture and sprinkle with quinoa (helps to absorb liquids). Place sliced zucchini overlapping a bit to create a single layer. Top with 1/3 of shredded chicken, then a bit of cheese (reserving a bit more than half for the top) and 1/3 of tomato sauce. Repeat until you run out of ingredients finishing with a layer of zucchini, topped with a bit of tomato sauce, then sprinkled with remaining cheese.
  • Bake covered with aluminum foil or silicone lid for 30 minutes, then uncover and bake for another 20 minutes.
  • Let stand for 20 minutes before slicing. Cut into 8 slices and serve hot.
🎉 Last step! If you made this recipe, please leave a review and let us know what you think!

Notes

  • Store: Refrigerate in an airtight glass container for up to 5 days.
  • Make ahead: Meal prep, assemble and refrigerate tightly covered for up to 24 hours. Meat is cooked, so it is safe. Then bake as per recipe.
  • Do not freeze:  Not ahead, nor the leftovers.

Nutrition

Serving: 1slice, Calories: 234kcal, Carbohydrates: 15g, Protein: 21g, Fat: 10g, Saturated Fat: 5g, Cholesterol: 59mg, Sodium: 458mg, Fiber: 3g, Sugar: 7g

Nutrition information is automatically calculated, so should only be used as an approximation.

Did you make this recipe?Mention @ifoodreal or tag #ifoodreal!
Olena cooking in her kitchen.

Watch Olena Cooking on Youtube

5 new videos every week

You may also like

About Olena

Welcome! I grew up in Ukraine watching my grandma cook with simple ingredients. I have spent the last 14 years making it my mission to help you cook quick and easy meals for your family!

Comments

  1. 5 stars
    I made this tonight for the family because I didn’t have much time and had many chicken breast and zucchinis. It was DELICIOUS. Everyone loved it.

    We are dairy free so I used Daiya shredded cheese in place of the cheese and added chopped cilantro to the enchilada sauce.

    Will make again!

  2. 5 stars
    You can make your own enchilada sauce, like store bought, but way better. Just add 2 TBLS oil, 2 TBLS flour,(cook for one minute) then add 4 TBLS Chili powder to the above sauce recipe. It will make a thicker more traditional sauce.

    1. 5 stars
      I love this recipe! I use leftover crock-pot taco chicken for my meat, and this suggestion for the enchilada sauce is spot-on!

  3. 5 stars
    OH MY YUM!!! I made this tonight and it was so flavorful and filling. Thank you for sharing this recipe. I will definitely be making this often.

    1. Zucchini doesn’t freeze well. It will be mushy, watery and stringy. I personally don’t like it and I’m not picky.

4.96 from 50 votes (7 ratings without comment)

Leave a Reply

Your email address will not be published. Required fields are marked *

Recipe Rating




This site uses Akismet to reduce spam. Learn how your comment data is processed.