Creamy chicken casserole always feels like a dish that knows how to listen. It doesn’t interrupt. It doesn’t show off. It just… shows up — warm, soft, and reliable in a way we all need sometimes. I started making this on a Sunday when I’d absolutely had it with the world. A bit of rain, no clean socks, and an inbox full of things I wasn’t emotionally ready for. But I had chicken, and I had cream. That’s all it took.
The first bite was one of those slow, eyes-closed, “yep, this’ll do” moments. It’s rich, but not in a showy way. The mushrooms bring earthiness, the lemon keeps it from feeling too heavy, and the chicken turns out so tender you’ll wonder why you ever settled for dry fillets. It’s the kind of dish that demands nothing but gives everything back.
Why You’ll Love It
- Comfort with a capital C — rich, creamy, and downright soothing.
- One dish wonder — great for leftovers, meal prep, or eating straight from the pan. No judgment.
- Easy but impressive — feels fancy but uses things you’ve probably already got.
- Flexible as anything — throw in peas, spinach, or just eat it as-is.
- Crowd-friendly — perfect for feeding friends, family, or just your own tired soul.
- Freezer gold — stash some away for a rainy day. Or a Wednesday.
Ingredients
For the chicken + mushrooms:
- 2½ lbs chicken breasts (around 4 to 5), cut into thick strips
- 1½ tsp sea salt
- ¼ tsp black pepper
- 1 cup plain flour
- 6 tbsp olive oil (divided)
- 1 lb white mushrooms, roughly sliced
- 1 onion, chopped fine
- 3 garlic cloves, minced
For the creamy sauce:
- 3 tbsp butter
- 3 tbsp flour
- 1½ cups chicken stock
- 1 tbsp lemon juice
- 1 cup half-and-half (or ½ cup whole milk + ½ cup cream)
- Salt + pepper, to taste
How to Make It
Dredge and brown the chicken:
Coat the chicken strips in flour, salt, and pepper. Heat 3 tbsp oil in a big pan, and brown the chicken in batches. Don’t try to do it all at once — you’ll end up steaming the poor things.
Sauté the mushrooms and onion:
Wipe the pan if it’s scorched. Add the rest of the oil, then mushrooms and onion. Let them soften and get golden — about 8 minutes. Stir in garlic for the last minute or two.
Make a roux that means business:
In a new pan (or the same one, if you’re a clean-as-you-go type), melt the butter. Whisk in flour and cook for a minute or so until it smells nutty and is just starting to colour.
Build the sauce:
Slowly add the stock, whisking like your life depends on it. Then the lemon juice. Then the half-and-half. Let it bubble gently until thick enough to coat a spoon. Season with a bit more salt and pepper.
Combine everything:
Place the chicken and mushroom mix into a large baking dish. Pour the sauce all over. You can give it a gentle stir or just let it settle as it bakes.
Bake and rest:
Cover with foil and bake at 350°F (180°C) for about 45 minutes. When it’s done, let it rest uncovered for 5 minutes to thicken slightly. I always forget this bit and end up with lava mouth.
Serve it up:
Perfect over mash, buttered rice, or with a bit of crusty bread. Or, honestly, a spoon straight from the baking dish if the day calls for it.
Common Mistakes and How to Dodge Them
My sauce is lumpy — what did I do?!
You probably rushed the stock in. Go slow with the whisk, and don’t skip cooking the flour first.
Chicken came out dry. Help.
Could be you sliced too thin or overcooked it. Keep the strips chunky and don’t skimp on foil during baking.
Why’s mine watery?
Either too much liquid or not enough thickener. Let it sit for a few minutes after baking — it’ll settle up nicely.
Needs more flavour?
More salt, more lemon, or even a pinch of mustard powder will lift it up. Don’t be afraid to tweak.
Storage and Reheating
- Fridge: Cool leftovers, store in a lidded container for up to 4 days.
- Freezer: Freeze in individual portions for up to 3 months. Defrost in the fridge overnight.
- Microwave: Reheat in short bursts, stirring in between. Add a splash of stock if it’s too thick.
- Oven: 180°C, covered, for 15–20 mins.
Frequently Asked Questions
Can I use chicken thighs instead of breasts?
Yes, and I’d even say they’re better — more flavour, more moisture, less chance of drying out.
Can I make this ahead of time?
Totally. Assemble everything the night before and bake when ready. Might need an extra 10 mins in the oven.
Do I have to use half-and-half?
Not at all. A combo of milk and cream works just fine. Don’t use only milk though — it won’t be creamy enough.
Can I add veggies?
Go for it. Spinach, frozen peas, or even broccoli would be brilliant stirred in just before baking.
Nutrition Facts (Per Serving):
- Calories: 447.4 kcal
- Fat: 21.5g
- Saturated Fat: 8.8g
- Cholesterol: 98.2mg
- Sodium: 874.2mg
- Potassium: 394.3mg
- Carbs: 29.6g
- Fibre: 0.8g
- Sugar: 3.2g
- Protein: 32.9g
Try More James Martin Recipes:
James Martin Creamy Chicken Casserole
Description
This cozy chicken casserole is creamy, rich, and packed with golden mushrooms, garlic, and lemon — perfect for warming up cold nights or feeding hungry people.
Ingredients
Instructions
- Dredge chicken in seasoned flour and brown in oil.
- Sauté mushrooms, onion, and garlic until golden.
- In a separate pan, make a roux with butter and flour. Slowly whisk in stock, lemon, and half-and-half.
- Combine chicken, mushrooms, and sauce in baking dish.
- Cover with foil and bake at 350°F for 45 minutes.
- Rest 5 minutes before serving.
Notes
- Don’t crowd the pan when browning chicken — it needs space to sear.
- Let the sauce thicken before combining, or it’ll be too runny.
- Want more zing? Add a bit of Dijon to the sauce.
- Works beautifully with chicken thighs too — just adjust cook time if bone-in.