Low Carb Chicken Spinach and Mushroom Oven Dish

Tender chicken, earthy mushrooms, fresh spinach, and plenty of creamy melted cheese come together in this comforting Low Carb Chicken Spinach and Mushroom Oven Dish.

Everything is baked together in one dish, creating a rich, savory dinner that’s satisfying without being loaded with carbohydrates. The mushrooms become tender and flavorful, the spinach melts into the creamy sauce, and the chicken stays juicy beneath a golden layer of cheese.

It’s a wonderful recipe for busy weeknights, meal prep, or whenever you’re craving a cozy casserole without pasta, rice, or potatoes.

❤️ Why You’ll Love This Recipe
Low carb and keto-friendly
High in protein
Creamy and cheesy
Packed with spinach and mushrooms
Easy one-dish preparation
Perfect for busy weeknights
Great for leftovers
Naturally gluten-free
Comfort food without the heavy carbs
📋 Recipe Information

Prep Time: 15 minutes

Cook Time: 30–35 minutes

Total Time: About 50 minutes

Servings: 6

Course: Dinner, Main Dish, Casserole

Cuisine: American, Low Carb

🛒 Ingredients
Chicken & Vegetables
2 pounds boneless, skinless chicken breasts, cut into bite-sized pieces
8 ounces mushrooms, sliced
5 ounces fresh baby spinach
2 tablespoons butter or olive oil
3 cloves garlic, minced
½ teaspoon salt
½ teaspoon black pepper
1 teaspoon Italian seasoning
Creamy Sauce
8 ounces cream cheese, softened
½ cup heavy cream
½ cup chicken broth
½ cup freshly grated Parmesan cheese
Cheese Topping
1½ cups shredded mozzarella cheese
½ cup shredded Parmesan cheese
🍳 Equipment Needed
9×13-inch baking dish
Large skillet
Cutting board
Sharp knife
Mixing spoon
Measuring cups and spoons
👩‍🍳 How to Make Low Carb Chicken Spinach and Mushroom Oven Dish
Step 1: Prepare the Oven

Preheat your oven to 375°F (190°C).

Lightly grease a 9×13-inch baking dish with butter or cooking spray.

Set aside.

Step 2: Brown the Chicken

Heat the butter or olive oil in a large skillet over medium-high heat.

Add the chicken pieces.

Season with salt, pepper, and Italian seasoning.

Cook for about 5–7 minutes, stirring occasionally, until the chicken is lightly browned on the outside.

It does not need to be completely cooked through yet.

Transfer the chicken to the prepared baking dish.

Step 3: Cook the Mushrooms

Using the same skillet, add the sliced mushrooms.

Cook for about 4–5 minutes, stirring occasionally, until they soften and release some of their moisture.

Add the minced garlic and cook for another 30–60 seconds.

Step 4: Wilt the Spinach

Add the fresh spinach to the skillet.

Cook for 1–2 minutes, stirring gently, until the spinach wilts.

Transfer the mushroom and spinach mixture to the baking dish with the chicken.

Spread everything into an even layer.

Step 5: Make the Creamy Sauce

Reduce the skillet heat to low.

Add the softened cream cheese, heavy cream, chicken broth, and Parmesan cheese.

Stir until the cream cheese melts and the mixture becomes smooth and creamy.

If the sauce seems too thick, add another tablespoon or two of chicken broth.

Step 6: Combine

Pour the creamy sauce over the chicken, mushrooms, and spinach.

Gently stir everything together in the baking dish so the sauce coats the ingredients evenly.

Step 7: Add the Cheese

Sprinkle the mozzarella evenly over the top.

Finish with the remaining Parmesan cheese.

The generous cheese topping will become beautifully golden and bubbly in the oven.

Step 8: Bake

Place the baking dish in the preheated oven.

Bake uncovered for approximately 25–30 minutes, or until the casserole is bubbling around the edges and the chicken reaches an internal temperature of 165°F (74°C).

For a more deeply golden top, broil for 1–2 minutes at the end, watching closely.

Step 9: Rest and Serve

Remove the casserole from the oven.

Let it rest for 5–10 minutes before serving.

This allows the creamy sauce to thicken slightly and makes the casserole easier to portion.

Serve warm.

💡 Tips for Success
Don’t Overcook the Chicken

Chicken breasts are lean, so cook them only until they reach 165°F (74°C). Overcooking can make them dry.

Brown the Mushrooms

Give the mushrooms enough time to release their moisture and develop some golden edges. This adds much more flavor to the finished casserole.

Use Freshly Grated Parmesan

Fresh Parmesan melts more smoothly into the sauce and gives the casserole a richer flavor.

Drain Extra Mushroom Liquid

If your mushrooms release a lot of liquid, let it cook off before adding them to the casserole. This helps keep the finished dish creamy rather than watery.

Let It Rest

A few minutes of resting time allows the sauce to settle and makes serving much easier.

🧀 Delicious Variations
Bacon Chicken Version

Add 6 slices of cooked, crumbled bacon to the chicken and spinach mixture before adding the sauce.

Extra Cheesy Version

Add another ½ cup of mozzarella or substitute some of the mozzarella with provolone or Monterey Jack.

Garlic Parmesan Chicken

Increase the garlic to 5 cloves and add an extra ¼ cup of Parmesan to the sauce.

Spicy Low Carb Chicken Bake

Add ¼ teaspoon crushed red pepper flakes or a little cayenne pepper to the creamy sauce.

Chicken Thigh Version

Replace the chicken breasts with boneless, skinless chicken thighs for a richer and juicier casserole.

🍽️ What to Serve With It

This casserole is filling enough to serve on its own, but it pairs beautifully with simple low-carb sides.

Try:

Cauliflower mash
Roasted asparagus
Steamed broccoli
Green beans
Zucchini noodles
Simple garden salad
Roasted cauliflower

For an extra creamy dinner, spoon the sauce from the casserole over cauliflower mash.

🥡 Storage Instructions
Refrigerator

Store leftovers in an airtight container in the refrigerator for up to 4 days.

Freezer

Allow the casserole to cool completely before freezing.

Freeze individual portions in airtight freezer-safe containers for up to 2 months.

The creamy sauce may change texture slightly after freezing and thawing.

Reheating

Reheat individual portions in the microwave in short intervals until hot.

For larger portions, cover with foil and warm in a 325°F (165°C) oven until heated through.

If the sauce has thickened, add a splash of chicken broth or heavy cream before reheating.

📊 Approximate Nutrition Information

Per serving, based on 6 servings:

Calories: 515
Protein: 48g
Fat: 32g
Carbohydrates: 8g
Fiber: 1g
Net Carbs: 7g

Nutrition is approximate and will vary depending on the chicken, dairy products, cheese, mushrooms, and other brands used.

❓ Frequently Asked Questions

Can I use frozen spinach?

Yes. Thaw it completely and squeeze out as much excess water as possible before adding it to the casserole.

Can I use chicken thighs?

Absolutely. Boneless, skinless chicken thighs are an excellent choice and will make the dish especially tender.

Can I make this ahead of time?

Yes. Assemble the casserole, cover it, and refrigerate for up to 24 hours before baking. Because the dish starts cold, you may need to add several minutes to the baking time.

Can I use different mushrooms?

Definitely. White button mushrooms, cremini, baby bella, or a combination all work well.

How can I make it even lower in carbs?

Use unsweetened, full-fat dairy products and check the labels on your chicken broth and seasonings for added sugars or starches.

Can I add bacon?

Yes! Crispy bacon is an especially delicious addition to the creamy chicken, spinach, and mushroom combination.

Why is my casserole watery?

Spinach and mushrooms both contain a lot of water. Wilt and drain spinach well, and cook mushrooms until most of their moisture has evaporated before assembling the casserole.

💚 Final Thoughts

This Low Carb Chicken Spinach and Mushroom Oven Dish is the kind of dinner that makes healthy eating feel anything but boring.

Tender chicken is surrounded by creamy Parmesan sauce, earthy mushrooms, tender spinach, and bubbling melted cheese. It’s rich, comforting, satisfying, and completely free of the pasta or rice you might normally expect in a creamy chicken casserole.