Creamy chicken stuffing casserole with mushrooms and green beans

The first time I made this casserole, the whole house smelled like Sunday dinner and soft blankets — kind of like a kitchen hug. I love how the warm, savory scent of mushrooms and sautéed onion drifts through the house while the stuffing crisps up on top; it feels like comfort on repeat. This dish combines juicy shredded chicken, tender green beans, earthy mushrooms, and a creamy, slightly tangy sauce, all tucked under a golden, crunchy stuffing crust. It’s the kind of recipe I reach for when I want something that feeds a crowd but still feels homey and familiar — the perfect midweek hero or potluck show-off.

Quick Facts

• Yield: Serves 6
• Prep Time: 20 minutes
• Cook Time: 40 minutes
• Total Time: 60 minutes

Why This Recipe is Awesome

This casserole marries creamy, savory sauce with a crunchy stuffing top — who doesn’t love a contrast of textures? It tastes rich without being fussy, and it smells like a cozy family dinner. The mushrooms add an earthy depth, the green beans give a fresh snap, and the stuffing soaks a bit of the sauce while still getting those crispy, golden edges. It’s so easy even your oven can’t mess it up (well, it can, but odds are good).

Ingredients

For the Main Dish:

• 1½ lb boneless, skinless chicken breasts (about 3 medium), cooked and shredded — or 3 cups rotisserie chicken, shredded
• 8 oz sliced mushrooms (white or cremini)
• 12 oz frozen green beans, thawed and patted dry (or 1 lb fresh, trimmed)
• 1 medium yellow onion, finely chopped (about 1 cup)
• 2 cloves garlic, minced
• 4 tbsp unsalted butter
• 3 tbsp all-purpose flour
• 2 cups chicken broth (low-sodium preferred)
• 1 cup sour cream or plain Greek yogurt
• ½ cup milk (or heavy cream for extra richness)
• 1 tsp Dijon mustard
• 1 tsp dried thyme (or 1 tbsp fresh)
• Salt and pepper, to taste
• 6 cups prepared stuffing (use a 6 oz boxed stuffing mix prepared per package, or 6 cups homemade crumbs)
• 2 tbsp melted butter (for tossing with stuffing)

For the Sauce / Garnish (if applicable):

• Optional: 2 tbsp grated Parmesan for sprinkling on top
• Fresh parsley, chopped, for garnish

How I Make It

Step 1:

Preheat the oven to 350°F and butter a 9×13-inch baking dish. I season the shredded chicken lightly with salt and pepper and set it aside. In a large skillet over medium heat, melt 2 tbsp butter and sauté the chopped onion until it becomes translucent and smells sweet — about 4 minutes. Add the minced garlic and cook 30 seconds until fragrant.

Step 2:

Push the onion and garlic to the side, add the remaining 2 tbsp butter, then toss in the sliced mushrooms. I like to let them sit for a minute so they sizzle and brown — that toasty, umami aroma makes me happy. Cook until the mushrooms dry out and turn golden, about 6–8 minutes.

Step 3:

Sprinkle the 3 tbsp flour over the veggies and stir for 1 minute to cook the raw flour taste away. Slowly pour in the 2 cups chicken broth, whisking so the sauce smooths out. Add the 1 cup sour cream, ½ cup milk, 1 tsp Dijon mustard, and 1 tsp thyme. Taste and adjust seasoning with salt and pepper. Let the sauce simmer and thicken for 2–3 minutes; it should coat the back of a spoon.

Step 4:

Stir the shredded chicken and thawed green beans into the sauce until everything looks well-coated and glossy. Spoon the mixture into the prepared baking dish and spread it evenly. Toss the prepared stuffing with 2 tbsp melted butter and sprinkle it in an even layer over the top.

Step 5:

Bake uncovered at 350°F for 25–30 minutes, until the casserole bubbles at the edges and the stuffing turns golden brown on top. If you like extra crisp, broil for 1–2 minutes while watching closely. Let it rest 5 minutes before serving so the sauce firms up a touch. Garnish with chopped parsley and a sprinkle of Parmesan if you like.

Pro Tips

• Use rotisserie chicken to cut prep time — it keeps the dish quick and flavorful.
• If your stuffing starts to brown too fast, tent the dish with foil for the first 15 minutes, then remove foil to crisp up the top.
• Swap sour cream for plain Greek yogurt for a tangy, protein-rich twist — just stir it in off heat to avoid curdling.
• For even browning, spread the stuffing in an even, not-too-thick layer so heat reaches it uniformly.

Common Mistakes to Avoid

• Skipping preheating: Classic rookie move. It changes texture and bake time.
• Overmixing: Leads to dense or chewy results. Mix until just combined.
• Guessing cook time: Always use visual cues or a timer, not just vibes.
• Overcrowding pans: Give your food some breathing room to crisp properly.

Alternatives & Substitutions

• Chicken ↔ tofu: Use 1½ lb extra-firm tofu, pressed and cubed, for a vegetarian swap — pan-fry until golden for better texture.
• Heavy cream swap: Use plain Greek yogurt or sour cream (off heat) for tang and thickness; it lightens the dish slightly.
• Gluten-free: Use a gluten-free stuffing mix or make a topping with crushed gluten-free crackers or cornflakes mixed with butter.
• Dairy-free: Replace butter with olive oil and sour cream with a dairy-free yogurt or coconut cream (note: coconut changes flavor).

Variations & Tips

• Spicy: Stir 1 tsp smoked paprika and a pinch of cayenne into the sauce for a warm kick.
• Kid-friendly: Omit mushrooms and use frozen peas instead of green beans for familiar flavors.
• Herb-forward: Add fresh rosemary and sage for a Thanksgiving-style twist.
• Cheesy: Mix 1 cup shredded sharp cheddar into the sauce for extra gooeyness.
• One-pan shortcut: Layer everything in a large ovenproof skillet, top with stuffing, then bake to save dishes.
• Creative twist: Swap stuffing for crushed buttery crackers and add a tablespoon of lemon zest to the sauce for a bright note.

FAQ (Frequently Asked Questions)

Can I make this ahead of time?

Yes! Assemble the casserole, cover, and refrigerate for up to 24 hours. When ready, bake from chilled and add 5–10 minutes to the bake time until bubbly and golden. For freezer prep, wrap tightly and freeze for up to 3 months; thaw overnight before baking.

Can I double the recipe?

Sure thing. Use a 9x13x2-inch or two 9×13 pans and increase bake time by about 10–15 minutes if the dish becomes deeper. Check for bubbling and a golden top.

Can I substitute butter with oil?

Technically yes, but you’ll miss that buttery magic. Use ¾ the amount of oil (so 3 tbsp oil for 4 tbsp butter) and choose a neutral oil like canola or avocado.

How do I know it’s done?

Look for bubbling around the edges, a thickened sauce, and a golden-brown stuffing top. The casserole should jiggle slightly but hold together when you scoop — and the chicken should be hot throughout.

What if I don’t have ingredient X?

Out of mushrooms? Use chopped zucchini or eggplant for earthiness. No sour cream? Stir in plain Greek yogurt or cream cheese (softened) for a similar creamy tang.

How I Like to Serve It

I serve this casserole with a crisp green salad and a tart vinaigrette to cut the richness — it brightens the plate. For drinks, a chilled glass of Riesling or a cold beer pairs nicely. This recipe fits weeknight dinners, casual potlucks, or cool-weather Sundays where you want comfort without fuss.

Notes

• Store leftovers in an airtight container for up to 4 days. Reheat in the oven at 350°F until warmed through, or microwave individual portions.
• Safe cooking temp for chicken: 165°F. If using freshly cooked chicken pieces, ensure they reach this temp before serving.

Final Thoughts

Closing: Now go impress someone — or just yourself — with your homemade masterpiece!