Old-School Green Bean Casserole

Featured in: Healthy Comfort Plates

This comforting casserole blends tender green beans with a savory mushroom sauce made creamy with butter, milk, and cream. Sautéed mushrooms and onions build rich flavor while the sauce thickens with flour and seasoning. The mixture is baked with crispy fried onions to create a golden, crunchy topping. This easy-to-make side brings nostalgic warmth to holiday meals or weeknight dinners, making vegetables irresistible with its creamy texture and savory depth.

Updated on Tue, 11 Nov 2025 13:52:00 GMT
A bubbly, golden-brown Old-School Green Bean Casserole with crispy onions, ready to eat. Pin It
A bubbly, golden-brown Old-School Green Bean Casserole with crispy onions, ready to eat. | fordish.com

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

I remember the first time my grandmother shared this casserole at our Thanksgiving table. It quickly became a beloved staple for every family gathering, and the crispy onions always remind me of shared laughter and tradition.

Ingredients

  • Fresh green beans: 900 g (2 lb), trimmed and cut into 5 cm (2-inch) pieces (or use 900 g frozen, 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:
Set oven to 180°C (350°F).
Prepare Green Beans:
Bring salted water to a boil. Add green beans and cook for 5 minutes until just tender but still bright green. Drain and rinse under cold water. Set aside.
Sauté Vegetables:
In a large skillet over medium heat, melt butter. Add mushrooms and cook 5-6 minutes until tender and browned. Add onion and garlic, cook 2-3 minutes until softened.
Make Sauce:
Stir in flour, 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.
Add Green Beans & Toss:
Add drained green beans to the skillet and toss to coat in sauce.
Assemble Casserole:
Transfer mixture to a 2-liter (2-quart) baking dish. Sprinkle half 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.
Cool & Serve:
Let cool for 5 minutes before serving.
Creamy, comforting Old-School Green Bean Casserole, a holiday favorite with tender green beans. Pin It
Creamy, comforting Old-School Green Bean Casserole, a holiday favorite with tender green beans. | fordish.com

This casserole always sparks memories—my family loves gathering in the kitchen to layer the topping and sneak a few onions before baking!

Required Tools

Large pot, colander, large skillet, whisk, 2-liter baking dish, oven

Allergen Information

Contains milk (dairy), wheat (gluten in flour and fried onions), soy (possible in store-bought fried onions). Double-check labels for fried onions and broth for allergens.

Nutritional Information

Per serving: 265 calories, 15 g total fat, 25 g carbohydrates, 6 g protein.

This classic Old-School Green Bean Casserole shows off a creamy sauce and crunchy onion topping. Pin It
This classic Old-School Green Bean Casserole shows off a creamy sauce and crunchy onion topping. | fordish.com

Serve warm for the classic old-school flavor everyone craves. The creamy sauce and crispy onions make this side dish unforgettable.

Recipe FAQs

Can frozen green beans be used instead of fresh?

Yes, frozen cut green beans can be substituted. Thaw and drain them before cooking to achieve the best texture.

What cheese can enhance the flavor?

Adding grated sharp cheddar or Gruyère to the sauce enriches the taste and adds depth to the creamy base.

How do I get crispy fried onions on top?

Use store-bought or homemade fried onions and add them halfway through baking and again at the end to keep them golden and crisp.

Is it possible to prepare this dish in advance?

Yes, assemble up to the baking step and refrigerate for up to 24 hours. Add onions and bake just before serving.

What sides pair well with this dish?

This creamy vegetable side complements roast turkey, chicken, or other hearty main courses nicely.

Old-School Green Bean Casserole

Creamy green beans and mushrooms topped with crispy fried onions for a comforting side.

Prep Time
15 minutes
Time to Cook
35 minutes
Overall Time
50 minutes
Recipe by Fordish Mia Harper


Skill Level Easy

Cuisine American

Result 6 Portion Size

Dietary Details Vegetarian Option

Ingredient List

Vegetables

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

Directions

Step 01

Preheat oven: Set oven temperature to 350°F.

Step 02

Blanch green beans: Boil salted water in a large pot. Add green beans and cook for 5 minutes until tender but bright. Drain and rinse under cold water to halt cooking.

Step 03

Sauté vegetables: Melt butter in a large skillet over medium heat. Add mushrooms and cook 5-6 minutes until browned. Stir in onion and garlic; cook 2-3 minutes until softened.

Step 04

Prepare sauce: Add flour to skillet, cook 1 minute while stirring. Gradually whisk in milk, cream, and broth. Simmer until thickened, about 5 minutes. Season with salt, pepper, and nutmeg if used.

Step 05

Combine beans and sauce: Add drained green beans to skillet and toss to coat evenly.

Step 06

Assemble casserole: Transfer mixture to a 2-quart baking dish. Sprinkle half of the fried onions on top.

Step 07

Bake first stage: Bake for 25 minutes until mixture is bubbly.

Step 08

Add topping and finish baking: Remove dish from oven, top with remaining fried onions, and bake 5-7 minutes until onions are golden and crisp.

Step 09

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

Tools Needed

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

Allergy Details

Review each ingredient for allergens. Ask your doctor if you’re unsure.
  • Contains milk (dairy), wheat (gluten), and possibly soy (check fried onions and broth labels).

Nutrition Details (each serving)

Values provided for reference. Consult your medical provider with questions.
  • Energy Value: 265
  • Lipids: 15 g
  • Carbohydrates: 25 g
  • Proteins: 6 g