Go Back

Zucchini Chicken Casserole With Mozzarella - A Cozy, Cheesy Weeknight Favorite

Print Recipe Pin Recipe
Prep Time 15 minutes
Cook Time 35 minutes
Total Time 50 minutes
Servings: 6 servings
Ingredients Method

Ingredients
  

  • 2 medium zucchinis, thinly sliced into half-moons
  • 1 1/2 pounds boneless, skinless chicken breasts, cut into bite-size pieces
  • 1 small yellow onion, finely diced
  • 3 cloves garlic, minced
  • 1 cup marinara sauce (or tomato basil sauce)
  • 1/2 cup chicken broth
  • 1/2 cup heavy cream (or half-and-half for lighter)
  • 1 1/2 cups shredded mozzarella cheese, divided
  • 1/4 cup grated Parmesan cheese
  • 2 tablespoons olive oil
  • 1 teaspoon Italian seasoning
  • 1/2 teaspoon crushed red pepper flakes (optional)
  • Salt and black pepper, to taste
  • Fresh basil or parsley, chopped, for garnish
  • Nonstick cooking spray or extra oil for the baking dish

Method
 

  1. Prep the oven and dish: Preheat the oven to 375°F (190°C). Lightly grease a 9x13-inch baking dish with cooking spray or olive oil.
  2. Season the chicken: Pat the chicken dry. Season with 1/2 teaspoon salt, 1/4 teaspoon black pepper, and half of the Italian seasoning.
  3. Sauté the chicken: Heat 1 tablespoon olive oil in a large skillet over medium-high. Add chicken and cook 4–6 minutes until lightly browned and just cooked through. Transfer to a plate.
  4. Cook the aromatics: In the same skillet, add the remaining 1 tablespoon olive oil. Sauté the onion for 3–4 minutes until soft. Add garlic and cook 30 seconds until fragrant.
  5. Build the sauce: Lower heat to medium. Stir in marinara, chicken broth, heavy cream, remaining Italian seasoning, and red pepper flakes. Simmer 2–3 minutes, then season to taste with salt and pepper.
  6. Par-cook the zucchini: Add the zucchini to the skillet and toss to coat. Cook 2–3 minutes, just until slightly tender but still crisp. Don’t overcook—they’ll bake further.
  7. Combine: Return the chicken to the skillet and fold in 1/2 cup shredded mozzarella and the Parmesan until just mixed.
  8. Assemble the casserole: Pour everything into the prepared baking dish and spread evenly. Top with the remaining 1 cup mozzarella.
  9. Bake: Bake uncovered for 18–22 minutes, until bubbly and the cheese is melted with golden spots.
  10. Rest and garnish: Let the casserole rest 5–10 minutes to set. Sprinkle with chopped basil or parsley before serving.