This is the casserole you make when you want dinner to taste like a hug. Tender chicken, buttery mushrooms, and a silky sauce come together under a golden, bubbly top. It’s simple enough for a weeknight and special enough for company.
The best part? Most of the work happens in one pan, and the oven does the heavy lifting. Serve it with a crisp salad or buttery noodles, and you’re set.
What Makes This Recipe So Good
- Deep, savory flavor: Mushrooms bring natural umami, while garlic, thyme, and a splash of white wine add restaurant-level depth.
- Creamy but balanced: A light cream sauce clings to the chicken without feeling heavy, thanks to chicken broth and a touch of Dijon.
- One-pan friendly: Sear, simmer, and bake in the same skillet for easy cleanup.
- Flexible: Use thighs or breasts, swap in different mushrooms, or add greens and grains.
- Make-ahead magic: Assemble earlier in the day and bake when you’re ready to eat.
Ingredients
- 1.5 pounds boneless, skinless chicken thighs or breasts, cut into large chunks
- 1 teaspoon kosher salt, plus more to taste
- 1/2 teaspoon black pepper
- 1/2 teaspoon smoked paprika (optional, for warmth)
- 2 tablespoons olive oil
- 2 tablespoons unsalted butter
- 1 medium yellow onion, finely chopped
- 3 cloves garlic, minced
- 12 ounces cremini or baby bella mushrooms, sliced
- 1 tablespoon fresh thyme leaves (or 1 teaspoon dried)
- 1/2 cup dry white wine (or extra chicken broth)
- 1 1/2 cups low-sodium chicken broth
- 1 tablespoon Dijon mustard
- 1/2 cup heavy cream (or half-and-half for lighter)
- 2 tablespoons all-purpose flour
- 1/2 cup grated Parmesan cheese, divided
- 1/2 cup shredded mozzarella or Gruyère
- 1/4 cup chopped fresh parsley
- Optional add-ins: 2 cups baby spinach, 1 cup cooked rice or egg noodles
Instructions
- Heat the oven: Preheat to 375°F (190°C).
Lightly grease a casserole dish if not finishing in the skillet.
- Season the chicken: Pat dry. Toss with salt, pepper, and smoked paprika.
- Sear the chicken: Heat olive oil in a large oven-safe skillet over medium-high. Add chicken in a single layer.
Sear 2–3 minutes per side until browned but not fully cooked. Transfer to a plate.
- Sauté aromatics: Reduce heat to medium. Add butter and onion; cook 3–4 minutes until translucent.
Stir in garlic for 30 seconds.
- Cook mushrooms: Add mushrooms and thyme. Cook 5–7 minutes, stirring occasionally, until browned and their liquid has mostly evaporated. Season with a pinch of salt.
- Deglaze: Pour in the white wine.
Scrape up browned bits; simmer 1–2 minutes until slightly reduced.
- Make the sauce: Whisk flour with 2 tablespoons of the broth to make a slurry. Stir Dijon into the skillet, then add remaining broth. Whisk in the slurry and simmer 2–3 minutes until lightly thickened.
Stir in cream and 1/4 cup Parmesan. Taste and adjust seasoning.
- Combine: Return chicken to the pan with any juices. If using, fold in spinach and cooked rice or noodles.
- Top and bake: Sprinkle mozzarella (or Gruyère) and remaining Parmesan over the top.
Transfer the skillet to the oven, or pour into the prepared casserole dish first. Bake 15–20 minutes, until bubbly and chicken is cooked through (165°F/74°C).
- Finish and serve: Rest 5 minutes. Shower with parsley and serve warm.
Keeping It Fresh
- Storage: Cool completely, then refrigerate in an airtight container for up to 4 days.
- Reheating: Warm gently on the stovetop over low heat or in a 325°F oven, covered, until hot.
Splash in a little broth or cream to loosen the sauce.
- Freezing: Freeze before baking for best texture. Wrap tightly and freeze up to 2 months. Thaw in the fridge overnight, then bake as directed, adding 5–10 extra minutes if needed.
- Make-ahead: Assemble up to 24 hours in advance.
Keep covered in the fridge and bake just before serving.
Health Benefits
- Lean protein: Chicken provides a solid protein boost, supporting muscle repair and steady energy.
- Mushroom perks: Mushrooms contribute B vitamins, selenium, and antioxidants with minimal calories.
- Balanced fats: Cream adds richness, but the sauce is stretched with broth. You can lighten with half-and-half or use less cheese.
- Portion control: This dish is satisfying, so smaller portions go a long way when paired with vegetables or a side salad.
Common Mistakes to Avoid
- Skipping the sear: Browning the chicken and mushrooms builds flavor and prevents a bland casserole.
- Overcrowding the pan: Cook chicken and mushrooms in batches if needed. Crowding steam-cooks instead of browning.
- Thin sauce: Let the sauce simmer until it lightly coats a spoon before baking.
A slurry helps set the texture.
- Overcooking chicken: Pull the casserole once the chicken hits 165°F. Overcooked chicken gets dry and stringy.
- Underseasoning: Taste the sauce before baking. A pinch of salt and a squeeze of lemon at the end can wake up the flavors.
Recipe Variations
- Herb swap: Use rosemary, sage, or tarragon in place of thyme for a different aroma.
- Mushroom mix: Combine cremini with shiitake or oyster mushrooms for deeper flavor.
- Lighter version: Use half-and-half, reduce cheese, and bulk it up with extra spinach or steamed cauliflower.
- Cheesy twist: Swap mozzarella for Gruyère, fontina, or provolone for a richer melt.
- Gluten-free: Use a gluten-free flour blend for the slurry and confirm your broth is GF.
- No wine: Replace with broth and add a teaspoon of lemon juice for brightness.
- Crispy topping: Mix panko with a little olive oil and Parmesan; sprinkle on top before baking.
FAQ
Can I use rotisserie chicken?
Yes.
Skip the searing step and fold shredded rotisserie chicken into the sauce before baking. Reduce bake time to 10–15 minutes since the chicken is already cooked.
What can I serve with this casserole?
Buttered egg noodles, mashed potatoes, or rice are classic. A simple green salad or roasted green beans keeps the meal balanced.
How do I prevent the sauce from curdling?
Keep the heat to a gentle simmer after adding cream, and avoid boiling.
Tempering the cream by warming it slightly before adding can also help.
Can I make this dairy-free?
Use olive oil instead of butter, a dairy-free cream alternative, and skip or replace the cheese with a plant-based option. Taste and adjust seasoning since dairy-free swaps can be milder.
Is it okay to use chicken breasts?
Absolutely. Breasts cook a touch faster than thighs, so watch the bake time and check for doneness at the 15-minute mark.
How do I thicken without flour?
Use a cornstarch slurry (1 tablespoon cornstarch mixed with 2 tablespoons cold water) added to the simmering sauce, then stir until it thickens.
Can I add vegetables?
Yes.
Spinach, peas, or sautéed leeks are great. Stir them in before baking so they warm through without overcooking.
In Conclusion
This Chicken Mushroom Casserole brings cozy comfort with simple ingredients and dependable technique. It’s creamy without being heavy, hearty without feeling fussy, and easy to adapt to what you have on hand.
Keep it in your rotation for busy nights, chilly weekends, or any time you want a warm, satisfying dinner with minimal fuss. One pan, familiar flavors, and a golden, bubbly finish—what’s not to love?