Amazing 40-Min Creamy Chicken and Mushroom One-Pan Casserole

Name: Amazing 40-Min Creamy Chicken and Mushroom One-Pan Casserole
Prep time: 10 min
Cook time: 30 min
Total time: 40 min
Cuisine: American
Ingredients: 4 boneless skinless chicken breasts, about 6 ounces each; 1/2 teaspoon salt; 1/2 teaspoon black pepper; 2 tablespoons olive oil; 2 tablespoons unsalted butter; 1 small onion, finely chopped; 3 cloves garlic, minced; 10 ounces cremini or white mushrooms, sliced; 1 tablespoon all-purpose flour; 1 cup chicken stock; 1/2 cup heavy cream; 1 teaspoon Dijon mustard; 1 teaspoon dried thyme or 1 tablespoon fresh thyme leaves; 1/4 cup grated Parmesan cheese; 2 tablespoons chopped parsley

By anna Boncoeur On August 15, 2025

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If you’re anything like me, you want dinner on the table fast but refuse to sacrifice that deeply satisfying, home-cooked flavor. That’s exactly where the Creamy Chicken and Mushroom One-Pan Casserole comes in! This recipe is my absolute go-to for those evenings when you need real comfort food without the mountain of dishes afterward. I’m Anna, and I’m obsessed with sharing simple, flavorful chicken recipes that make everyday cooking feel joyful and totally achievable, even on a Tuesday.

I’ve spent years perfecting skillet meals that taste like they took hours. This casserole truly delivers that rich, savory mushroom cream sauce blanketing tender chicken. It’s proof that you can get restaurant-quality results using just one deep pan. Seriously, forty minutes from start to finish—it’s magic, and I can’t wait for you to try it!

Table Of content

Why You’ll Love This Creamy Chicken and Mushroom One-Pan Casserole

I know what it’s like when 5 PM hits and you’re staring into the fridge, wondering how you’re going to feed everyone something delicious without dirtying half the kitchen. This recipe solves that problem beautifully. It’s designed specifically for the home cook who values speed just as much as taste. Trust me, once you taste that savory sauce, you’ll understand why this skillet dinner is making its way into heavy rotation at your house.

Here are the reasons why this dish is such a winner for busy weeknights:

Incredibly Fast Prep: We’re talking just 10 minutes of chopping and seasoning before the cooking even starts. It moves fast!
The Ultimate One-Pan Wonder: Everything happens right in that large skillet—searing, sautéing, simmering. That means cleanup is a breeze, usually just the pan, a cutting board, and a few utensils.
Deep Comfort Flavor: The combination of seared chicken, earthy mushrooms, thyme, and that luxurious Parmesan cream sauce hits every comforting note you could want from a great casserole.
Weeknight Reliability: This recipe is forgiving and consistent. It always comes out perfectly tender and flavorful, making it a safe bet for any stressful evening.

Quick Prep and Minimal Cleanup

The true genius here is the one-pan method. We sear the chicken first to lock in all those lovely brown bits—that’s pure flavor gold—and then we build the entire sauce right on top of those bits in the same pan. You don’t transfer anything until you serve it! This saves you scrubbing pots later. Since the chicken finishes simmering right in the sauce, it stays incredibly moist, and you get this fantastic, concentrated flavor profile that you just can’t achieve if you cook everything separately.

Essential Equipment for Your Creamy Chicken and Mushroom One-Pan Casserole

To make this one-pan wonder work its magic, you need the right vessel. Since we are searing, sautéing, and simmering all in one place, the size and depth of your pan matter a lot. Don’t try to squeeze this into a shallow frying pan—you need room for that sauce to bubble happily around the chicken!

Required Cookware

A large, deep, oven-safe skillet (10 or 12 inches is perfect). If you don’t have an oven-safe one, just make sure it has a tight-fitting lid for simmering.
A sharp knife and cutting board for all that chopping.
A sturdy whisk for smoothing out the sauce later.
Tongs for turning the chicken breasts during searing.
A reliable instant-read meat thermometer—this is non-negotiable for chicken safety!

Ingredients for the Creamy Chicken and Mushroom One-Pan Casserole

Alright, let’s talk ingredients! Since this is a one-pan meal, every single component really has to pull its weight, and I think this list does the job perfectly. We’re using four good-sized chicken breasts here, which feeds four hungry people generously. Make sure you have your onion finely chopped and your garlic minced because we want those flavors to release quickly when we start cooking.

The mushrooms are the star of the sauce, so slicing them thinly helps them cook down nicely and release their moisture. And notice the thyme—I prefer using fresh leaves if I have them because the aroma is incredible, but dried works just fine if that’s what you have on hand. It all comes together beautifully!

Ingredient Breakdown

Ingredient	Quantity (Yield: 4 Servings)	Preparation
Boneless Skinless Chicken Breasts	4 (about 6 ounces each)	Whole
Salt	1/2 teaspoon	Divided use
Black Pepper	1/2 teaspoon	Divided use
Olive Oil	2 tablespoons
Unsalted Butter	2 tablespoons
Onion	1 small	Finely chopped
Garlic	3 cloves	Minced
Cremini or White Mushrooms	10 ounces	Sliced
All-Purpose Flour	1 tablespoon
Chicken Stock	1 cup
Heavy Cream	1/2 cup
Dijon Mustard	1 teaspoon
Dried Thyme	1 teaspoon	Or 1 tablespoon fresh thyme leaves
Grated Parmesan Cheese	1/4 cup
Fresh Parsley	2 tablespoons	Chopped, for garnish

Step-by-Step Instructions for the Creamy Chicken and Mushroom One-Pan Casserole

This is where the magic happens, and trust me, keeping everything in one pan makes the process feel so streamlined. We start by getting that beautiful sear on the chicken, which builds the flavor foundation for the entire Creamy Chicken and Mushroom One-Pan Casserole. Don’t rush this step—those golden bits are your friends!

Searing the Chicken

First things first: pat those chicken breasts really dry with paper towels. Seriously, dry surface equals great sear! Sprinkle both sides generously with half of your salt and pepper. Get your large, deep skillet heating over medium-high heat, and add the olive oil. You know it’s ready when the oil shimmers lightly. Carefully lay the chicken breasts in the pan—don’t crowd them! Sear them for about 3 to 4 minutes per side. We aren’t cooking them all the way through here, just getting that gorgeous golden-brown crust. Once they look nicely colored, pull them out onto a clean plate and set them aside. They’ll finish cooking later in the sauce.

Building the Mushroom Cream Sauce Base

Turn the heat down to medium. Now, melt your butter right into that hot skillet—scrape up any little brown bits left from the chicken while the butter melts; that’s instant flavor! Toss in your finely chopped onion and cook it gently for about 3 minutes until it starts looking soft and translucent. Add the minced garlic next, but watch it closely; it only needs about 30 seconds to get fragrant before it burns. Next up are the mushrooms! Add all 10 ounces of sliced mushrooms and let them cook, stirring occasionally, for about 5 to 6 minutes. You want them to brown up and give off most of their water. This concentrates their earthy flavor beautifully. Now, sprinkle the tablespoon of flour over the vegetables and stir it constantly for one full minute. This cooks out the raw flour taste and creates our roux. Slowly pour in the chicken stock, whisking constantly to make sure no lumps form. Once it’s smooth, stir in the heavy cream, Dijon mustard, and thyme. Let this mixture bubble gently until it starts to thicken slightly.

Finishing the Creamy Chicken and Mushroom One-Pan Casserole

It’s time to bring it all home! Gently nestle the seared chicken breasts back into the skillet, making sure they sit nicely in that simmering sauce. Spoon some of that delicious sauce right over the top of each piece of chicken. Reduce the heat to medium-low, cover the pan if you need to (or just let it simmer uncovered), and let everything gently cook for about 10 minutes. This is the most crucial safety step: use your thermometer to check the thickest part of the chicken. It must read 165°F internally for safety. Once it hits that magic number, turn off the heat. Stir in the Parmesan cheese until it melts smoothly into the sauce, making this Creamy Chicken and Mushroom One-Pan Casserole incredibly rich. Sprinkle with fresh parsley and serve your stunning Creamy Chicken and Mushroom One-Pan Casserole immediately!

Tips for Success with Your Creamy Chicken and Mushroom One-Pan Casserole

Listen, even the simplest skillet dinner can sometimes throw you a curveball, especially when you’re dealing with sauces. But honestly, this recipe is so forgiving! Just focus on a couple of key moments, and you’ll have that perfect restaurant texture every single time. Don’t let the cream throw you off; we’ve got easy fixes for common wobbles.

Achieving Perfect Sauce Consistency

The biggest sauce hiccup is usually lumps when adding the stock, or the sauce being too thin at the end. Remember, you have to cook that flour for a full minute after stirring it in—that’s crucial for thickening! If, after simmering with the chicken, your sauce still seems too thin, just take the lid off and let it bubble away over medium-low heat for a few extra minutes. The heavy cream will reduce beautifully. If you accidentally add too much stock and it gets watery, just whisk in another half teaspoon of flour mixed with a teaspoon of cold water (a slurry) and let it simmer for two minutes to thicken up again.

Searing for Flavor Depth

If you skip the sear, you’re missing half the flavor! When you take the chicken out, there will be dark brown bits stuck to the bottom of your pan—those are called fond, and they are flavor bombs. When you add the butter and then the stock, you must scrape every bit of that fond up; that’s how you build the depth for your sauce. Also, please, please, use that thermometer when the chicken goes back in. We need that 165°F internal temperature for safety, and it keeps the chicken perfectly tender without drying it out.

Serving Suggestions for This Creamy Chicken and Mushroom One-Pan Casserole

This rich, savory sauce was just begging to be soaked up by something wonderful! Since this is a low-carb recipe naturally, it’s fantastic served over a bed of fluffy white rice or creamy mashed potatoes—those are my family’s favorites. If you’re watching carbs, don’t worry; this is also amazing spooned over zucchini noodles or tender egg noodles. If you want to see more of my favorite ways to serve up delicious meals, check out my Pinterest board!

We usually have a simple green salad on the side, maybe tossed with a bright vinaigrette, just to cut through the richness of the cream sauce. It’s a complete meal right there in the skillet, ready in under an hour!

Storing and Reheating Leftovers

Good news! This skillet dinner reheats beautifully, which is perfect for meal prepping lunch the next day. Because the sauce is cream-based, you just need to be gentle when warming it up so it doesn’t break or get too oily. I always aim for slow and low heat when reheating to keep that creamy texture intact.

Storage Guidelines

Storage Type	Duration	Reheating Method
Refrigerated	Up to 3 days	Gentle simmer or microwave

If you’re reheating on the stovetop, add just a splash of extra chicken stock or milk to loosen the sauce up before bringing it to a very low simmer until heated through. Don’t let it boil rapidly!

Frequently Asked Questions about This Skillet Dinner

I get so many questions about tweaking my favorite recipes, and that’s totally fair! Cooking should be flexible. Since this is such an easy chicken recipe to adapt, I wanted to clear up a few common concerns people have when they first try this skillet dinner.

Can I use chicken thighs instead of breasts?

Oh, absolutely! Chicken thighs are actually fantastic here because they have more fat, meaning they stay incredibly tender and juicy even if you accidentally leave them simmering for an extra minute or two. If you use thighs, you might need to add 2 to 3 minutes to the simmering time to ensure they reach that safe 165°F internal temperature. Just remember to sear them well first for that great flavor!

How do I make this a lower-fat option?

If you’re looking to cut back on fat, the heavy cream is the easiest place to start. You can substitute the 1/2 cup of heavy cream with half-and-half, though the sauce will be slightly thinner. For a bigger change, you can use Greek yogurt, but you must temper it first! Whisk a spoonful of the hot pan liquid into the yogurt separately before stirring the yogurt into the pan right at the end when the heat is off. This prevents it from curdling.

What if I do not have fresh thyme?

Don’t stress! I always keep dried thyme in my spice rack for exactly these situations. The conversion is simple: use 1 teaspoon of dried thyme for every 1 tablespoon of fresh thyme the recipe calls for. If you have fresh thyme leaves, that’s even better—use 1 tablespoon of those fresh leaves instead of the dried amount. The flavor will be brighter!

Share Your Creamy Chicken and Mushroom One-Pan Casserole Experience

I truly hope this Creamy Chicken and Mushroom One-Pan Casserole makes your weeknights a little easier and a lot more delicious! If you tried this recipe out, I’d love to hear what you thought. Did you serve it over rice or noodles? Let me know how it turned out for you in the comments below, and don’t forget to leave a quick rating so other busy cooks can find this easy chicken recipe!