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Old-School Green Bean Casserole

Featured in: Comfort Cravings

This dish blends tender green beans with a savory mushroom sauce, enriched by cream and milk, then topped with golden crispy fried onions. The green beans are briefly blanched for bright color and crisp-tender texture before being combined with a comforting, thickened sauce. The casserole is baked until bubbling and finished with a final layer of crispy onions, adding satisfying crunch and flavor. Rich, smooth, and nostalgic, it pairs wonderfully with roast poultry and festive meals.

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Updated on Sun, 09 Nov 2025 13:41:00 GMT
Creamy Old-School Green Bean Casserole topped with crispy onions, perfect for holiday gatherings. Save
Creamy Old-School Green Bean Casserole topped with crispy onions, perfect for holiday gatherings. | sugarprairie.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 is exactly how I remember it from childhood celebrations, with a rich sauce and just the right crunch. Every time I make it, it brings back cozy family memories and wins over new fans at the table.

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
  • Small yellow onion: 1, 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.
Sauté Vegetables:
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.
Make 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 & Sauce:
Add the drained green beans to the skillet and toss to coat evenly in the sauce.
Transfer & Top:
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 & Serve:
Let cool for 5 minutes before serving.
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| sugarprairie.com

We always had this on our holiday table, and even picky eaters loved it. Passing the dish around with family makes for special memories every single year.

Recipe Variations

Add grated sharp cheddar or Gruyère cheese to the sauce for extra richness, or try using sautéed leeks instead of onions for a twist.

Serving Suggestions

Pairs beautifully with roast turkey, chicken, or as part of a vegetarian feast. It also complements mashed potatoes and cranberry sauce.

Allergen & Nutrition Info

Contains milk and wheat. Check fried onion and broth labels for soy and other potential allergens. Each serving has 265 calories, 15 g fat, 25 g carbohydrates, and 6 g protein.

Nostalgic Old-School Green Bean Casserole served piping hot with mushrooms and savory sauce. Save
Nostalgic Old-School Green Bean Casserole served piping hot with mushrooms and savory sauce. | sugarprairie.com

This classic casserole always disappears quickly at gatherings. Make it once and it will become a must-have for your future holidays.

Kitchen Help

→ How do I prepare the green beans before baking?

Green beans should be boiled in salted water for about 5 minutes to become tender yet crisp, then immediately cooled in cold water to halt cooking and preserve their bright green color.

→ Can I use frozen green beans instead of fresh?

Yes, frozen cut green beans can be thawed and drained before using, offering a convenient alternative without compromising texture.

→ What ingredients create the creamy sauce?

The sauce combines sautéed mushrooms, onions, garlic, butter, flour for thickening, whole milk, heavy cream, and vegetable broth, seasoned with salt, pepper, and optional nutmeg.

→ How should the crispy fried onions be added?

Half of the fried onions are layered over the green bean mixture before baking; the rest are sprinkled on top near the end of baking to achieve maximum crispiness.

→ Can this dish be prepared in advance?

Yes, assemble through step six and refrigerate up to 24 hours. Add the topping and bake just before serving for best results.

→ What are good pairing options for this side?

This creamy casserole pairs especially well with roast turkey or chicken, making it a great choice for holiday meals or family dinners.

Old-School Green Bean Casserole

Tender green beans in a creamy mushroom sauce topped with crispy onions for a holiday side.

Setup duration
15 min
Heat duration
35 min
Complete duration
50 min
Created by Molly Evans

Classification Comfort Cravings

Complexity Easy

Heritage American

Output 6 Portions

Nutrition guidelines Meat-free

Components

Vegetables

01 2 lb fresh green beans, trimmed and cut into 2-inch pieces (or substitute with 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 steps

Phase 01

Preheat Oven: Set oven temperature 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 tender yet bright green. Drain and rinse under cold water to halt cooking. Set aside.

Phase 03

Sauté Vegetables: In a large skillet over medium heat, melt butter. Add mushrooms and cook for 5 to 6 minutes until browned and tender. Add onion and garlic and cook for an additional 2 to 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 for about 5 minutes until sauce thickens. Season with salt, black pepper, and nutmeg, if using.

Phase 05

Combine Beans and Sauce: Add the drained green beans to the skillet and toss to coat thoroughly with the sauce.

Phase 06

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

Phase 07

Bake First Stage: Bake for 25 minutes until the mixture is bubbling.

Phase 08

Add Topping and Finish Baking: Remove from oven, evenly spread the remaining fried onions over the surface, then bake for an additional 5 to 7 minutes until golden and crispy.

Phase 09

Rest Before Serving: Allow the dish to cool for 5 minutes before serving.

Kitchen tools needed

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

Dietary concerns

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

Dietary breakdown (per portion)

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