There is something deeply comforting about pulling a bubbling casserole out of the oven, especially when it smells rich and garlicky. This creamy keto chicken casserole has become one of those dependable dinners in my kitchen that everyone quietly hopes I’ll make again.

It’s hearty without feeling heavy, creamy without being overwhelming, and full of flavor in every bite. I love that it works just as beautifully for a regular weeknight as it does when friends come over.

The sauce wraps around the chicken and mushrooms in the most satisfying way. And once you spoon it onto a plate with something simple on the side, dinner suddenly feels complete.

My kids always go back for seconds when I make this. They adore that creamy texture and the tender baked chicken, and honestly, I do too.

Why This Dish Works So Well

This casserole balances richness and freshness in a way that keeps it interesting. The heavy cream and parmesan bring depth, while lemon juice and parsley keep everything from tasting flat.

The mushrooms soak up the sauce and become golden and savory. Paired with juicy chicken, it turns into a dish that feels generous and satisfying without needing anything fancy.

I also appreciate how flexible it is. Chicken breasts, tenders, or thighs all work here, so I simply use what I have.

Ingredients Needed for the Recipe

• Chicken breast, tenders, or chicken thighs (770 g / 27 oz) – The heart of the dish. Boneless and skinless pieces bake up tender and soak in all the creamy sauce.
• Salt – Enhances every layer of flavor, from the chicken to the sauce.
• Ground paprika (1 tsp) – Adds warmth and a gentle smoky note to the chicken.
• Pepper – Brings subtle heat and balance.
• Onion (80 g / 2.8 oz) – Creates a sweet, savory base once caramelized.
• Garlic (1/4 tsp) – Gives that unmistakable depth that makes the sauce irresistible.
• Mushrooms (500 g / 17.6 oz, halved) – Add earthiness and absorb the creamy sauce beautifully.
• Heavy whipping cream (1 cup / 220 ml) – Forms the rich and silky base of the sauce.
• Parmesan cheese (1/2 cup / 50 g) – Half seasons the chicken, half thickens and flavors the sauce.
• Chicken broth or water (1 cup / 220 ml) – Loosens the sauce and builds savory depth.
• Lemon juice (2 tbsp) – Brightens the creaminess and prevents the dish from feeling too heavy.
• Nutmeg (1/4 tsp) – A small pinch adds warmth and subtle complexity.
• Parsley (1 tbsp, chopped) – Fresh finish that adds color and a clean taste.

Choosing the Right Chicken

If I want a leaner option, I reach for chicken breasts or tenders. They cook quickly and slice neatly when serving.

On days when I want extra juiciness, I go with thighs. They stay tender and forgiving, even if baked a little longer.

Just make sure the pieces are roughly similar in size. That small detail helps everything cook evenly.

How to make Creamy keto chicken casserole?

Step 1 – Season the Chicken

Start by patting the chicken dry. Season both sides with salt, pepper, and ground paprika, then sprinkle half of the grated parmesan directly onto the chicken.

This layer of parmesan melts slightly during searing and forms a flavorful coating. It’s simple, but it makes a difference.

Step 2 – Sear Until Golden

Heat olive oil in a skillet over medium heat. Place the chicken in the hot pan and cook until golden brown on both sides.

You’re not cooking it through yet. Just build that golden crust and flavor before transferring it to a baking dish.

Step 3 – Transfer to the Casserole Dish

Arrange the browned chicken in a casserole dish, about 26 x 17 x 7 cm. Keep the pieces snug but not stacked.

This allows the sauce to flow around each piece later. Every bite should be coated.

Step 4 – Saute Onion and Garlic

Using the same skillet with the remaining oil, add chopped onion and garlic. Cook until the onion turns golden and slightly caramelized.

This step builds the base of the sauce. The sweetness from the onion balances the cream perfectly.

Step 5 – Cook the Mushrooms

Add the halved mushrooms with a small pinch of salt. Let them cook until soft and lightly browned on the edges.

They will release moisture first, then begin to caramelize. That’s when the flavor really develops.

Step 6 – Create the Creamy Sauce

Pour in the heavy whipping cream and chicken broth. Add lemon juice, nutmeg, and the remaining parmesan cheese.

Stir gently and let it simmer for 2 to 3 minutes. The sauce will thicken slightly and become silky.

Step 7 – Combine and Prepare for Baking

Pour the hot creamy mushroom mixture over the chicken in the casserole dish. Spoon some sauce over each piece.

Everything should be evenly distributed so the chicken stays moist while baking.

Step 8 – Bake Until Tender

Cover the dish and bake in a preheated oven at 175C or 350F for about 30 minutes.

The chicken will finish cooking gently in the sauce, becoming incredibly tender and infused with flavor.

Step 9 – Garnish and Serve

Once out of the oven, sprinkle chopped parsley over the top. That little pop of green makes the dish feel fresh.

Serve warm with a crisp salad or mashed cauliflower. The sauce spooned over the side is always welcome.

Serving Ideas

This casserole pairs beautifully with simple sides. I often serve it with mashed cauliflower because it soaks up every drop of that creamy sauce.

A light cucumber salad or leafy greens with olive oil also works well. The freshness balances the richness on the plate.

If you’re serving guests, place the casserole dish right on the table. It feels warm and inviting, and everyone can help themselves.

Tips

• Do not overcrowd the skillet when searing the chicken. Brown it in batches if needed.
• Let the mushrooms cook long enough to caramelize slightly for deeper flavor.
• Taste the sauce before baking and adjust salt if necessary.
• Cover the casserole while baking to keep the chicken juicy.
• Freshly grated parmesan melts better and tastes stronger than pre-shredded.
• If the sauce feels too thick, add a splash of broth before baking.

Storage and Meal Prep

This creamy keto chicken casserole stores very well. I often make it ahead because the flavors deepen overnight.

Keep leftovers in an airtight container in the refrigerator for up to three days. Reheat gently on the stove or in the oven so the sauce stays smooth.

It also works beautifully for meal prep. Divide into portions and pair with vegetables for easy lunches during the week.

Sometimes I even double the recipe when I know the week will be busy. It saves time and keeps everyone happy.