Name: Creamy Green Bean Casserole with Mushrooms, Fried Onions, and Parmesan Recipe
Prep time: 10 min
Cook time: 45 min
Total time: 55 min
Cuisine: American
Ingredients: 1 lb fresh green beans, rinsed, trimmed and halved; 8 ounces cremini or white mushrooms, sliced; 3 garlic cloves, minced; 3 tablespoons unsalted butter, divided; 1 cup vegetable or chicken broth; 1 cup heavy cream; 1/4 cup parmesan cheese, finely grated; 1/2 teaspoon kosher salt; 1/4 teaspoon pepper; 2 tablespoons flour; 2 cups fried onions, divided; 1/4 cup panko bread crumbs

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If you’re craving a timeless classic that delivers comfort and elegance in every bite, this Creamy Green Bean Casserole with Mushrooms, Fried Onions, and Parmesan Recipe is exactly what you need. It strikes a perfect balance between velvety cream sauce, tender crisp green beans, earthy mushrooms, and that irresistible crunch of fried onions topped with toasted panko and Parmesan. Whether you’re gathering for a holiday feast or just longing for a hearty side dish, this casserole brings warmth and flavor to your table in such a lovable way that you’ll keep coming back for more.

Ingredients You’ll Need

The image shows a flat lay of ingredients for a dish arranged neatly on a white marbled surface. There are nine clear and white bowls and plates, each holding different items: a large glass bowl with bright green cut green beans, a glass bowl with sliced white mushrooms, a small white bowl with finely minced garlic, another small white bowl filled with a white powder (flour), a small scalloped white bowl with shredded cheese, a small white bowl with light-colored round crumbs, and a small white plate with three yellow butter pieces. A glass measuring cup containing a brown liquid is at the center. Two copper spoons hold salt and black pepper. At the bottom left, a white bowl holds golden-brown crispy fried onion rings. The whole layout is clean and bright with natural light casting soft shadows, photo taken with an iphone --ar 4:5 --v 7

These ingredients are the stars of this dish, each bringing something special to the mix — from the freshness of green beans to the rich creaminess of heavy cream and the delightful crunch from the fried onions and panko breadcrumbs. Simple yet essential, every component helps transform this green bean casserole from ordinary to extraordinary.

1 lb fresh green beans: Rinsed, trimmed, and halved for that ideal tender-crisp texture.
3 tablespoons unsalted butter: Divided use to enrich flavors and toast crumbs perfectly.
8 ounces cremini or white mushrooms: Sliced, they add deep, earthy notes and meaty texture.
1/2 teaspoon kosher salt: Enhances the overall taste without overwhelming.
1/4 teaspoon pepper: Adds just a whisper of heat and depth.
3 garlic cloves, minced: Elevate the savory profile with subtle aromatic warmth.
2 tablespoons flour: Essential for thickening the creamy mushroom sauce.
1 cup vegetable or chicken broth: Builds the base of the sauce and adds complexity.
1 cup heavy cream: Creates that luscious, dreamy texture we all love in casseroles.
2 cups fried onions: Divided use for mixing into the casserole and adding crispy topping.
1/4 cup panko bread crumbs: Toasted to deliver a golden, crunchy contrast.
1/4 cup parmesan cheese, finely grated: Sprinkled on top to bring a sharp, nutty finish.

How to Make Creamy Green Bean Casserole with Mushrooms, Fried Onions, and Parmesan Recipe

Step 1: Prepare the Green Beans

Start by bringing a large pot of salted water to a boil. Blanch the green beans for 3 to 4 minutes until they’re vibrant and just slightly tender. This quick boil locks in their freshness and bright green color. Immediately transfer them to a bowl of ice water to halt the cooking process—this keeps them crisp and perfectly textured for the casserole. Drain and dry them thoroughly with a kitchen or paper towel for the best results.

Step 2: Sauté the Mushrooms

In a large skillet, melt 2 tablespoons of butter over medium heat. Add the sliced mushrooms along with the kosher salt and pepper. Cook for about five minutes, stirring occasionally, until the mushrooms release their moisture and brown beautifully. Add the minced garlic and cook for an additional two minutes to infuse the buttery mixture with fragrant garlic goodness.

Step 3: Make the Creamy Sauce

Sprinkle the flour evenly over the mushrooms and stir to coat. This step thickens the sauce later, ensuring a rich consistency. Slowly pour in the broth, stirring constantly to avoid lumps, and let it simmer for 2 to 3 minutes. Reduce the heat and gradually mix in the heavy cream, stirring gently until the sauce thickens into a velvety smooth dream — this usually takes 5 to 10 minutes. Remove from the heat once perfectly thickened.

Step 4: Combine Ingredients in the Baking Dish

Stir the blanched green beans and 1 cup of fried onions into your creamy mushroom sauce until everything is evenly coated and mouthwateringly mixed. Pour this mixture into a greased 9 x 13-inch baking pan, spreading it out evenly as you prepare for the crowning toppings.

Step 5: Toast the Panko Breadcrumbs

In a medium skillet, melt the remaining 1 tablespoon of butter over medium heat. Toss in the panko breadcrumbs and toast them for 3 to 4 minutes, stirring frequently until golden and fragrant. Season with salt and pepper to enhance that irresistible crunch.

Step 6: Add Toppings and Bake

Sprinkle the remaining fried onions, toasted panko breadcrumbs, and finely grated Parmesan cheese evenly over the casserole. Bake uncovered at 375 degrees Fahrenheit for about 20 minutes, until the casserole bubbles happily and the topping is a gorgeous golden brown. Pull it from the oven and get ready to savor every spoonful.

How to Serve Creamy Green Bean Casserole with Mushrooms, Fried Onions, and Parmesan Recipe

The dish is a baked green bean casserole in a white rectangular dish. The bottom layer is creamy light beige sauce mixed with fresh green beans that are bright green and cut into pieces, and some slices of brown mushrooms. The top layer is full of crispy golden brown fried onion rings scattered unevenly, adding a crunchy texture, with some shredded light yellow cheese sprinkled on top. A silver spoon is scooping out some casserole, showing layers clearly. The dish rests on a white marbled surface with a blue and white striped cloth nearby. Photo taken with an iphone --ar 4:5 --v 7

Garnishes

For a beautiful finishing touch, consider sprinkling freshly chopped parsley or chives atop the casserole just before serving. These bright green herbs add a pop of color and a subtle freshness that contrasts wonderfully with the creamy depth of the casserole.

Side Dishes

This casserole pairs spectacularly with roasted turkey or chicken, making it a standout during festive meals. Alternatively, serve it alongside mashed potatoes or a crisp winter salad to balance its rich flavors with lighter, refreshing notes.

Creative Ways to Present

For a charming presentation, scoop the creamy green bean casserole into individual ramekins or small cast-iron skillets. This not only impresses your guests but also creates inviting single servings that make the dish feel extra special at your dinner table.

Make Ahead and Storage

Storing Leftovers

Leftovers of this Creamy Green Bean Casserole with Mushrooms, Fried Onions, and Parmesan Recipe keep beautifully in an airtight container in the refrigerator for up to 3 days. The flavors actually blend even more after resting, making for delicious second-day servings.

Freezing

If you want to save some for later, freeze the casserole before baking in a freezer-safe dish, covered tightly with foil and plastic wrap. It freezes well for up to 2 months. When ready to enjoy, defrost overnight in the fridge for best texture and taste.

Reheating

Reheat individual portions in the microwave or thawed casserole in a preheated oven at 350 degrees Fahrenheit until warmed through and bubbly once more. To revive the crisp topping, broil for a minute or two watching carefully so it doesn’t burn.

FAQs

Can I use frozen green beans instead of fresh?

Absolutely, frozen green beans can be a convenient substitute. Just thaw and drain them well before using to avoid excess moisture, which can affect the casserole’s texture.

Is it possible to make this casserole vegetarian?

Yes! Use vegetable broth instead of chicken broth, and ensure your fried onions do not contain animal-derived ingredients. This keeps the dish rich and flavorful without any meat.

How do I get the fried onions extra crispy on top?

For an ultra-crispy topping, combine the fried onions with toasted panko breadcrumbs and sprinkle freshly grated Parmesan. Baking uncovered at a high temperature helps them brown perfectly.

Can I prepare the mushroom sauce ahead of time?

You can make the mushroom sauce a day ahead and store it in the refrigerator. Reheat gently before combining with beans and assembling the casserole to save time on the day of serving.

What can I use if I don’t have panko breadcrumbs?

Regular breadcrumbs or crushed crackers can work in a pinch, but panko offers a lighter, airier crunch that elevates the topping’s texture beyond expectations.

Final Thoughts

There’s something truly comforting and special about this Creamy Green Bean Casserole with Mushrooms, Fried Onions, and Parmesan Recipe that makes it a treasured classic for holidays and everyday dinners alike. Its blend of creamy sauce, tender green beans, savory mushrooms, and golden, crunchy topping is the kind of dish that feels like a warm hug on a plate. I wholeheartedly encourage you to try it yourself—you’ll find it’s a surefire way to bring smiles to your table and make mealtime feel memorable and delicious every time.