Old-School Green Bean Casserole

Featured in: Easy Comfort Recipes

This classic holiday side features tender green beans enveloped in a creamy mushroom sauce, topped with crispy fried onions for texture and flavor. Fresh green beans are lightly cooked then combined with sautéed mushrooms, onions, and garlic in a rich sauce made from butter, cream, and broth. After baking until bubbling, extra fried onions add a satisfying crunch atop the dish. Ideal for family dinners and festive occasions.

Updated on Sat, 15 Nov 2025 16:56:00 GMT
Creamy, classic Old-School Green Bean Casserole with golden crispy onions, perfect for a cozy Thanksgiving. Save to Pins
Creamy, classic Old-School Green Bean Casserole with golden crispy onions, perfect for a cozy Thanksgiving. | spicra.com

A nostalgic, creamy side dish featuring tender green beans, savory mushrooms, and crispy fried onions—a classic for holiday feasts and family dinners.

This green bean casserole always takes me back to family gatherings, where the dish would be passed around and everyone clamored for seconds. It's been a staple on our holiday table for as long as I can remember!

Ingredients

  • Fresh green beans: 900 g (2 lb), trimmed and cut into 5 cm (2-inch) pieces (or substitute with 900 g frozen cut green beans, thawed and drained)
  • Unsalted butter: 2 tbsp
  • Cremini or button mushrooms: 250 g (9 oz), sliced
  • Yellow onion: 1 small, finely chopped
  • Garlic cloves: 2, minced
  • All-purpose flour: 2 tbsp
  • Whole milk: 240 ml (1 cup)
  • Heavy cream: 120 ml (½ cup)
  • Low-sodium vegetable broth: 120 ml (½ cup)
  • Salt: 1 tsp
  • Black pepper: ½ tsp
  • Ground nutmeg (optional): ½ tsp
  • Crispy fried onions: 150 g (1½ cups), store-bought or homemade

Instructions

Preheat Oven:
Preheat the oven to 180°C (350°F).
Cook Green Beans:
Bring a large pot of salted water to a boil. Add green beans and cook for 5 minutes until just tender but still bright green. Drain and immediately rinse under cold water to stop cooking. Set aside.
Prepare Sauce Base:
In a large skillet over medium heat, melt the butter. Add mushrooms and cook for 5-6 minutes until tender and browned. Add onion and garlic, cooking for another 2-3 minutes until softened.
Thicken Sauce:
Stir in the flour and cook for 1 minute, stirring constantly. Gradually whisk in milk, cream, and broth. Bring to a simmer and cook until thickened, about 5 minutes. Season with salt, pepper, and nutmeg (if using).
Combine Beans and Sauce:
Add the drained green beans to the skillet and toss to coat evenly in the sauce.
Assemble and Add Onions:
Transfer the mixture to a 2-liter (2-quart) baking dish. Sprinkle half of the crispy fried onions on top.
Bake:
Bake for 25 minutes until bubbling. Remove from oven, top with remaining onions, and bake for 5-7 minutes more until golden and crisp.
Rest and Serve:
Let cool for 5 minutes before serving.
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My kids always ask for extra crispy onions on their portion, and it's become a family tradition to let them sprinkle the last layer before popping it back in the oven.

Make Ahead & Storage

You can assemble the casserole (leave off the onions) up to a day in advance and refrigerate. Add onions just before baking and bake as directed until hot and bubbly.

Serving Suggestions

This classic side is perfect for Thanksgiving, Christmas, or any potluck. It pairs beautifully with roast turkey, chicken, or even hearty vegetarian mains.

Nutritional Info

Each serving provides approximately 265 calories, 15 g total fat, 25 g carbohydrates, and 6 g protein. Nutritional values may vary depending on specific brands of fried onions and dairy used.

Tender green beans are coated in a rich mushroom sauce in this Old-School Green Bean Casserole, topped with crispy onions. Save to Pins
Tender green beans are coated in a rich mushroom sauce in this Old-School Green Bean Casserole, topped with crispy onions. | spicra.com

This old-school casserole is pure comfort and guaranteed to earn you rave reviews at the table. Enjoy every bite of this creamy, crunchy classic!

Questions & Answers

Can frozen green beans be used?

Yes, thawed and drained frozen green beans work well and save prep time without sacrificing texture.

How do you make the sauce creamy?

The sauce gains creaminess from a combination of butter, flour, milk, and heavy cream gently cooked to thicken before adding the green beans.

What’s the best way to get crispy fried onions?

Store-bought crispy fried onions are convenient, but homemade ones can be made by frying thinly sliced onions in oil until golden and crunchy.

Can cheese be added for extra flavor?

Yes, grated sharp cheddar or Gruyère added to the sauce enriches the taste and adds depth.

How should the dish be reheated to maintain crispiness?

Reheat in the oven until warmed through to keep the topping crisp instead of microwaving which can make it soggy.

Old-School Green Bean Casserole

Tender green beans with savory mushrooms and crispy fried onions baked to golden perfection.

Prep Time
15 min
Time to Cook
35 min
Overall Time
50 min
Recipe by spicra Olivia Carter

Dish Category Easy Comfort Recipes

Skill Level Easy

Cuisine Type American

Makes 6 Number of Servings

Dietary Details Vegetarian-Friendly

What You'll Need

Vegetables

01 2 lb fresh green beans, trimmed and cut into 2-inch pieces (or 2 lb frozen cut green beans, thawed and drained)

Sauce Base

01 2 tbsp unsalted butter
02 9 oz cremini or button mushrooms, sliced
03 1 small yellow onion, finely chopped
04 2 garlic cloves, minced
05 2 tbsp all-purpose flour
06 1 cup whole milk
07 ½ cup heavy cream
08 ½ cup low-sodium vegetable broth
09 1 tsp salt
10 ½ tsp black pepper
11 ½ tsp ground nutmeg (optional)

Topping

01 1½ cups crispy fried onions (store-bought or homemade)

Cooking Steps

Step 01

Preheat oven: Set oven temperature to 350°F.

Step 02

Blanch green beans: Bring a large pot of salted water to a boil. Cook green beans for 5 minutes until tender-crisp and bright green. Drain and rinse under cold water to halt cooking. Set aside.

Step 03

Sauté mushrooms and aromatics: In a large skillet over medium heat, melt butter. Sauté mushrooms for 5 to 6 minutes until browned and tender. Add onion and garlic; cook 2 to 3 minutes until softened.

Step 04

Prepare sauce: Sprinkle flour over the mixture and cook, stirring constantly, for 1 minute. Gradually whisk in milk, heavy cream, and vegetable broth. Simmer until sauce thickens, about 5 minutes. Season with salt, pepper, and optional nutmeg.

Step 05

Combine beans with sauce: Add drained green beans to the skillet and toss carefully to coat them evenly with the sauce.

Step 06

Assemble casserole: Transfer mixture into a 2-quart baking dish. Evenly sprinkle half of the crispy fried onions on the surface.

Step 07

Bake first stage: Bake for 25 minutes until the casserole bubbles.

Step 08

Add topping and finish baking: Remove from oven, evenly scatter remaining fried onions over the top, and return to oven for 5 to 7 minutes until golden brown and crisp.

Step 09

Rest before serving: Allow casserole to cool for 5 minutes before serving.

Necessary Tools

  • Large pot
  • Colander
  • Large skillet
  • Whisk
  • 2-quart baking dish
  • Oven

Allergy Details

Go through each ingredient to spot allergens. If unsure, reach out to a healthcare provider.
  • Contains milk (dairy), wheat (gluten in flour and fried onions), and potentially soy (in commercial fried onions). Verify ingredient labels for allergens.

Nutrition Info (each portion)

For informational use only—please talk to your doctor for health advice.
  • Calorie Count: 265
  • Fats: 15 g
  • Carbohydrates: 25 g
  • Proteins: 6 g