This creamy chicken casserole is the kind of meal I come back to again and again, especially when I want something comforting without a lot of fuss. It’s hearty, familiar, and made with ingredients that usually already live in my fridge.

I love recipes like this because they feel flexible and forgiving. You can cook it once and stretch it into two completely different dinners, which honestly feels like a small win on a busy week.

The base is simple: chicken, vegetables, stock, and cream, all cooked together until everything is tender and cosy. Nothing flashy here, just solid, dependable comfort food that actually tastes like it took effort.

When I first made this creamy chicken casserole, I served it with mashed potatoes one night, then turned the leftovers into a puff pastry-topped pie the next. Same dish, totally different mood, and no one complained.

It’s filling without being heavy, rich without being overwhelming, and it works just as well for family dinners as it does for stocking the freezer. That balance is what makes it a keeper in my kitchen.

Ingredients Needed for the Recipe

• Olive oil – Used to gently sauté the vegetables and build flavour right from the start.
• Onion – Forms the savoury base of the casserole and adds natural sweetness as it cooks.
• Carrots – Bring colour, subtle sweetness, and a bit of texture to the dish.
• Celery – Adds depth and balances the richness of the creamy sauce.
• Garlic – Gives the casserole warmth and that familiar, comforting aroma.
• Butter – Helps create a rich base for the sauce and carries flavour.
• Flour – Thickens the sauce and gives it a silky, casserole-style consistency.
• Chicken stock – Forms the backbone of the sauce and keeps everything savoury.
• Chicken breast – A lean, affordable protein that stays tender when cooked in sauce.
• Frozen peas – Stirred in at the end for freshness and a pop of green.
• Cream – Brings richness and that unmistakable creamy finish.
• Cornflour – Helps thicken the casserole right at the end without heaviness.
• Mashed potato – The perfect companion for soaking up every bit of sauce.
• Italian parsley – Adds freshness and a simple finishing touch.

I like that none of these ingredients are hard to find or overly expensive. This is real, everyday cooking, the kind you can pull together without a special shopping trip.

How to make Creamy Chicken Casserole?

Step 1 – Soften the vegetables

Start by preheating your oven to 180°C fan bake so it’s ready when you are. Heat a large, oven-safe casserole dish over medium heat and add the olive oil.

Add the onion, carrot, and celery, then sauté them gently for about five minutes. You’re not looking for colour here, just soft vegetables and a fragrant base.

Step 2 – Build the sauce base

Stir in the crushed garlic and let it cook briefly until fragrant. Push the vegetables aside slightly and add the butter to the centre of the dish.

Once the butter is melted and bubbling, sprinkle over the flour and stir it through. Let it cook for a couple of minutes to remove that raw flour taste.

Step 3 – Add stock and chicken

Pour in about half of the chicken stock and use a wooden spoon to scrape up any bits from the bottom. This step adds flavour and keeps nothing stuck.

Add the remaining stock, then stir in the diced chicken breast. Everything should be just covered in liquid and looking slightly creamy already.

Step 4 – Bake until tender

Place the lid on the casserole dish and transfer it to the oven. Bake for 45 minutes, allowing the chicken to cook gently and the flavours to meld.

This slow, enclosed cooking keeps the chicken breast tender, which is especially helpful since it’s such a lean cut.

Step 5 – Finish with cream and peas

Remove the dish from the oven and stir in the peas and cream. Mix the cornflour with cold water, then add it to the casserole and stir well.

Return the dish to the oven uncovered and cook for another 15 minutes. The sauce will thicken and take on that classic creamy casserole texture.

Step 6 – Season and serve

Once thickened, season generously with salt and pepper. Taste and adjust if needed, then serve hot over mashed potato.

Finish with a sprinkle of fresh parsley for colour and a little freshness. Simple, satisfying, and ready to eat.

Serving Ideas

Mashed potato is my go-to here, especially on colder nights when comfort is non-negotiable. The sauce sinks into the mash and makes every bite better.

If you want something lighter, this casserole also works beautifully with steamed rice or even buttered pasta. Both soak up the sauce without competing for attention.

Baked potatoes are another solid option, especially if you like a bit of texture contrast. Spoon the casserole over the top and let it spill naturally.

For leftovers, turning this into a pie is where things get really fun. Puff pastry on top transforms it into a completely new dinner.

Tips

• Dice the chicken evenly so it cooks at the same rate and stays tender.
• Don’t rush the vegetable step; soft onions make a big difference to flavour.
• Stir the flour well into the butter to avoid lumps later.
• Always mix cornflour with cold water before adding it to the dish.
• Season at the end so you don’t overdo the salt as the sauce reduces.
• Let the casserole sit for a few minutes before serving to thicken slightly.

Variations and Simple Swaps

This creamy chicken casserole is very forgiving when it comes to vegetables. If you don’t have carrots or celery, other options work just as well.

Mushrooms add a deeper, savoury note and pair beautifully with the cream. Leeks can replace onions for a softer, sweeter flavour.

You can also use frozen mixed vegetables if that’s what you have on hand. They’re convenient and surprisingly good in casseroles like this.

If you prefer a slightly lighter sauce, you can reduce the cream and replace part of it with extra stock. The result is still creamy, just a bit gentler.

For a pie version, let the casserole cool slightly before adding puff pastry. This helps the pastry stay crisp and bake evenly.

Storage and Make-Ahead Notes

This casserole stores beautifully, which is one of the reasons I make it so often. Leftovers can be kept in an airtight container in the fridge for up to three days.

Reheat gently on the stovetop or in the microwave until piping hot. Add a splash of stock if the sauce has thickened too much.

It also freezes well, making it ideal for batch cooking. Let it cool completely before freezing to keep the texture just right.

If you plan to freeze it as a pie, do so before baking the pastry. Thaw fully before cooking, then bake until golden and bubbling.

This kind of flexibility makes weeknight dinners easier and a lot less stressful. One good recipe, used well, goes a long way.

I come back to this creamy chicken casserole because it always delivers. It’s warm, filling, and adaptable, which is exactly what I want from a recipe that earns a permanent spot in my rotation.