Introduction

This Chicken Zucchini Casserole is a hearty and creamy dish that combines tender chicken, sautéed vegetables, and a cheesy sauce. It’s perfect for a comforting weeknight dinner that feels both wholesome and satisfying.

The close-up image shows a creamy baked casserole in a white rectangular dish, filled with chunky pieces of browned chicken, thick slices of toasted mushrooms, and green zucchini pieces. The dish is topped with melted, golden-brown cheese that looks gooey and slightly crisp around the edges. Small bits of chopped herbs are scattered across the surface, adding a fresh green touch. A wooden spoon scoops up a portion, showing the mix of tender meat and vegetables layered under the cheesy top. The dish sits on a white marbled surface, with a dark gray cloth nearby. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 lb boneless skinless chicken breast (cut into 1-inch pieces)
3/4 tsp sea salt (divided into 1/2 tsp and 1/4 tsp)
1/2 tsp black pepper (divided)
2 tbsp olive oil (divided)
8 oz mushrooms (sliced)
1/2 large onion (diced)
3 medium zucchini (cut into half-moons)
1/2 cup heavy cream
1/3 cup chicken broth, reduced sodium
6 oz Swiss Gruyere shredded cheese blend (or just one type; divided)
1/2 cup sour cream

Instructions

Step 1: Place the chicken pieces in a large bowl and pat dry with paper towels. Season with 1/2 teaspoon of salt and 1/4 teaspoon of pepper.
Step 2: Heat 1 tablespoon of olive oil in a 12-inch skillet over medium-high heat. Add the chicken and sear for 5-6 minutes, turning every couple of minutes to brown all sides until cooked through. Remove the chicken to a large bowl, cover to keep warm, and set aside.
Step 3: Add the remaining 1 tablespoon of olive oil to the same pan and reduce heat to medium. Add mushrooms and onions, cooking for 7-10 minutes until mushrooms are soft and liquid has evaporated.
Step 4: Increase heat to medium-high and add zucchini. Season with remaining 1/4 teaspoon salt and 1/4 teaspoon pepper. Sauté, stirring occasionally, for about 10 minutes until zucchini is soft and lightly browned. Drain any remaining liquid.
Step 5: Transfer the cooked vegetables to the bowl with chicken and set aside.
Step 6: Preheat oven to 400°F (191°C).
Step 7: In the same skillet, add heavy cream and chicken broth. Scrape the bottom to release browned bits, then bring to a boil over medium-high heat. Simmer for about 5 minutes until the sauce thickens enough to coat the back of a spoon.
Step 8: Reduce heat to low and stir in 3 ounces of shredded cheese until melted. Remove from heat and stir in sour cream. Season with salt and pepper to taste if needed.
Step 9: Drain any liquid from the chicken and vegetable mixture if present, then pour the sauce over and mix to combine.
Step 10: Transfer everything to a 10×7-inch casserole dish. Sprinkle the remaining 3 ounces of shredded cheese on top.
Step 11: Bake for about 10 minutes until the cheese is melted. For a golden top, broil for 2-3 minutes if desired.

Tips & Variations

Use a mix of Swiss and Gruyere cheese for a richer flavor, or substitute with mozzarella for a milder taste.
Swap chicken for turkey or tofu for a different protein option.
Adding fresh herbs like thyme or rosemary during cooking enhances the aroma and flavor.
For extra texture, sprinkle some toasted breadcrumbs on top before baking.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently in the microwave or oven until warmed through. Avoid overheating to prevent drying out the chicken and vegetables.

How to Serve

The image shows a baked casserole in a white rectangular dish, with two main layers visible on top. The bottom layer has cooked slices of green zucchini and browned mushrooms, both soft and textured, mixed with pieces of browned chicken. The top layer is melted, golden-brown cheese that covers most of the vegetables and chicken, bubbling slightly at the edges and sprinkled with small green parsley leaves for color. The dish sits on a white marbled surface, with fresh zucchini and a small wooden bowl of chopped parsley nearby. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use frozen chicken for this recipe?

It’s best to use fresh or fully thawed chicken breast to ensure even cooking and maintain texture.

Can I prepare this casserole ahead of time?

Yes, you can assemble it a day in advance and store it in the refrigerator. Bake just before serving, adding a few extra minutes to the cooking time if needed.