Old-School Green Bean Casserole

Featured in: Seasonal Favorites

This nostalgic side features fresh green beans simmered until tender and combined with sautéed mushrooms, onion, and garlic in a creamy sauce made from butter, milk, cream, and broth. The mixture is baked and finished with a crunchy topping of golden fried onions, offering layers of texture and savory depth. Ideal for festive meals or comforting family dinners, it blends richness and freshness in every bite.

Updated on Thu, 13 Nov 2025 15:59:00 GMT
Creamy Old-School Green Bean Casserole with golden onions, a comforting American classic, ready to serve. Save
Creamy Old-School Green Bean Casserole with golden onions, a comforting American classic, ready to serve. | tazzsip.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 casserole brings back warm memories of family gatherings and festive meals. I first made it for a Thanksgiving dinner and every guest asked for seconds because it was so flavor-packed and familiar.

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:
Set oven to 180°C (350°F).
Blanch beans:
Bring a large pot of salted water to a boil. Add green beans and cook for 5 minutes until just tender. Drain and rinse under cold water. Set aside.
Sauté mushrooms and aromatics:
In a large skillet over medium heat, melt butter. Add mushrooms and cook for 5-6 minutes until browned. Add onion and garlic, cook for 2-3 minutes until softened.
Make sauce:
Stir in 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.
Combine beans and sauce:
Add drained green beans to skillet and toss to coat evenly in the sauce.
Assemble casserole:
Transfer 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.
Serve:
Let cool for 5 minutes before serving.
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Every Thanksgiving, my aunt and I share this dish and recall stories from past family feasts. Even the kids request extra helpings, making it a cherished staple at our table.

Required Tools

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

Allergen Information

Contains milk (dairy), wheat (flour and fried onions), and possible soy in store-bought fried onions. Always double-check labels if you are sensitive.

Nutritional Information

Per serving: Calories 265, Total Fat 15 g, Carbohydrates 25 g, Protein 6 g

Imagine a bubbly Old-School Green Bean Casserole: tender beans in a rich sauce, topped with crispy onions. Save
Imagine a bubbly Old-School Green Bean Casserole: tender beans in a rich sauce, topped with crispy onions. | tazzsip.com

This casserole is guaranteed to delight any crowd. Try it for your next holiday gathering—it's easy, timeless, and honestly irresistible.

Recipe Guide

Can frozen green beans be used instead of fresh?

Yes, frozen green beans can be substituted. Thaw and drain them thoroughly before cooking to ensure proper texture.

How is the creamy sauce thickened?

The sauce is thickened by cooking flour with butter before gradually whisking in milk, cream, and vegetable broth until it simmers and thickens.

What is the purpose of rinsing green beans after boiling?

Rinsing under cold water stops the cooking process, preserving the bright color and crisp-tender texture of the beans.

Can this dish be prepared in advance?

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

Is there a way to add extra flavor to the dish?

Adding grated sharp cheddar or Gruyère cheese to the sauce enriches the flavor and creates a more indulgent texture.

Old-School Green Bean Casserole

Tender green beans and mushrooms in a rich, creamy sauce topped with crispy fried onions.

Setup duration
15 min
Heat duration
35 min
Complete duration
50 min
Created by Daniel Brooks

Classification Seasonal Favorites

Complexity Easy

Heritage American

Output 6 Portions

Nutrition specifications Meat-free

Components

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)

Method

Phase 01

Preheat Oven: Preheat the oven to 350°F.

Phase 02

Blanch 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 rinse under cold water to halt cooking. Set aside.

Phase 03

Cook Mushrooms and Aromatics: In a large skillet over medium heat, melt butter. Add mushrooms and cook for 5-6 minutes until tender and browned. Add onion and garlic, cooking an additional 2-3 minutes until softened.

Phase 04

Prepare Sauce: Stir in flour and cook for 1 minute, stirring constantly. Gradually whisk in milk, heavy cream, and vegetable broth. Simmer until thickened, about 5 minutes. Season with salt, pepper, and nutmeg if using.

Phase 05

Combine Green Beans and Sauce: Add the drained green beans to the sauce in the skillet and toss to coat evenly.

Phase 06

Assemble Casserole: Transfer mixture to a 2-quart baking dish. Sprinkle half of the crispy fried onions evenly over the top.

Phase 07

Bake with Topping: Bake in preheated oven for 25 minutes until bubbling. Remove, top with remaining fried onions, and bake an additional 5-7 minutes until golden and crisp.

Phase 08

Rest Before Serving: Allow to rest for 5 minutes before serving.

Necessary tools

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

Allergy details

Review ingredients carefully for potential allergens and seek professional medical guidance when uncertain.
  • Contains milk (dairy), wheat (gluten in flour and fried onions), and possibly soy in store-bought fried onions. Verify ingredient labels accordingly.

Dietary information (per portion)

Values shown are estimates only - consult healthcare providers for specific advice.
  • Energy: 265
  • Fats: 15 g
  • Carbohydrates: 25 g
  • Proteins: 6 g