Vegetable Chicken Breast Casserole

Subscribe to our newsletter!

Stay informed with our newsletter! Sign up to receive updates on new recipes and culinary articles. Plus, after subscription, you get a FREE sample of the cookbook “10 Common Mistakes Anyone Can Make In The Kitchen” (download link provided in the Welcome email.)

Vegetable Chicken Breast Casserole

Vegetable Chicken Casserole with Mushrooms and Roasted Peppers

This Vegetable Chicken Breast Casserole is a culinary delight that marries tender chicken breasts with an array of savory vegetables, resulting in a dish that's both comforting and bursting with flavor. Cooked to perfection in the oven, it features succulent chicken, earthy mushrooms, and roasted peppers, with the added depth of onions and chopped tomatoes.
The chicken breast is the star of this casserole, providing a lean and protein-rich foundation, while the mushrooms and roasted peppers contribute a medley of enticing textures and tastes. Onions and chopped tomatoes infuse the casserole with a delightful, savory sweetness.
Topping it all off is a decadent layer of melted cheese, adding a luscious finish to this culinary masterpiece. Whether prepared as a hearty family dinner or as a special dish for gatherings, this casserole promises a satisfying dining experience that marries wholesome ingredients with indulgent richness.
Prep Time 15 minutes
Cook Time 1 hour
Total Time 1 hour 15 minutes
Course Main Course
Cuisine American
Servings 12 servings


  • 50/1.5 (oz/kg) skinless boneless chicken breast
  • 50/1.5 (oz/kg) red bell peppers; you can replace them with 35 oz/1 kg roasted bell peppers to save time.
  • 17/500 (oz/g) yellow onions
  • 28/800 (oz/g) canned chopped tomatoes
  • 17/500 (oz/g) canned mushrooms
  • 2 tbsp olive oil
  • 7/200 (fl oz/ml) lukewarm water or chicken stock
  • some salt and ground black pepper to taste
  • 1 tsp garlic powder or 2-3 garlic cloves, chopped finely
  • 10/300 (oz/g) grated cheese (Parmesan, Cheddar, or another similar cheese type)


  • roast the red bell peppers by your preferred method.
  • wait 30 minutes to cool the peppers, then peel them and remove the stubs and seeds.
  • chop the peppers into smaller pieces or strips.
  • cube the boneless skinless chicken breast.
  • peel and chop the onions finely.
  • pour olive oil into a frying pan.
  • sear the chicken breast until bleached.
  • put the chicken breast into a heat-proof casserole.
  • fry the onions until glassy in the same pan as the chicken.
  • add and simmer the well-drained mushrooms.
  • add and simmer the baked peppers for a few minutes.
  • add and simmer the tomatoes for a few minutes.
  • pour water or chicken stock into the pan.
  • season with salt and ground black pepper.
  • add the garlic and simmer ingredients until the sauce lowers about 1/3.
  • add the vegetables together with the sauce over the chicken into the casserole.
  • bake the chicken casserole at 180C/360F for about 30 minutes.
  • add the grated cheese into an even layer.
  • bake the chicken casserole at 250C/480F until golden on top (about 15-20 minutes.)
  • stop the heat and let the dish to rest 15-30 minutes before serving.



Cooking Tips for the Best Results:

1. Sear the Chicken for Flavor: Start by searing the chicken breasts in a hot pan before assembling the casserole. This step locks in the chicken’s juices and adds a delicious, golden crust for extra flavor.
2. Evenly Slice Ingredients: To ensure that the casserole cooks evenly, take the time to slice the mushrooms, roasted peppers, and onions into consistent sizes. This promotes balanced cooking and distribution of flavors.
3. Layer Ingredients Thoughtfully: When assembling the casserole, layer the ingredients thoughtfully. Begin with a base of chicken, followed by the mixture of mushrooms, roasted peppers, and onions, ensuring that each layer is seasoned and evenly distributed.
4. Monitor Cheese Melting Carefully: When adding the cheese layer on top, monitor the casserole closely to prevent over-browning. If needed, cover the casserole with foil for part of the cooking time to ensure that the cheese melts evenly without becoming too crispy.
5. Rest Before Serving: After removing the casserole from the oven, allow it to rest for a few minutes. This resting period lets the flavors meld and ensures that the chicken remains tender and juicy.

How useful was this post?

Click on a star to rate it!

Average rating / 5. Vote count:

No votes so far! Be the first to rate this post.

As you found this post useful...

Follow us on social media!

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

FAQs about the Vegetable Chicken Breast Casserole Recipe

Can I use boneless, skinless chicken thighs instead of chicken breasts?

Yes, boneless, skinless chicken thighs are a suitable alternative. They offer a slightly different texture and flavor but work well in this casserole.

What type of cheese is best for the topping?

Cheddar, mozzarella, or Swiss cheese are excellent choices for the cheese topping. They melt well and add a delightful creamy finish to the casserole.

Can I prepare this casserole in advance and bake it later?

Yes, you can assemble the casserole in advance and refrigerate it until you’re ready to bake. Just be sure to adjust the cooking time if the dish is cold from the fridge.

What sides go well with this casserole?

This casserole pairs wonderfully with sides like steamed vegetables, a green salad, or crusty bread. These accompaniments balance the richness of the casserole and complete the meal.

Can I freeze leftovers of this casserole for later consumption?

Yes, you can freeze leftovers. Store them in an airtight container, and they should keep for up to 2-3 months. Thaw and reheat in the oven for the best results.

Related Chicken Breast Casserole Recipes and Culinary Articles

➡️ Your search for a skinless boneless chicken breast recipe that turns into a delicious meal is over! Enjoy cooking baked chicken breast casserole from scratch. For additional info, read more here.

📖 Cooking article by