Old-School Green Bean Casserole

Featured in: One-Pot Comfort Meals

This classic green bean casserole offers tender green beans enveloped in a creamy sauce made from mushrooms, butter, and a hint of garlic. Its rich texture is topped with crunchy fried onions baked to golden perfection, creating a balance between softness and crispness. Ideal for holiday dinners, the dish brings a comforting, savory flavor that pairs beautifully with roasted poultry or other mains. Simple to prepare, it combines fresh ingredients and creamy sauce for satisfying results.

Updated on Tue, 11 Nov 2025 15:09:00 GMT
Golden-brown Old-School Green Bean Casserole topped with crispy fried onions, ready to be served. Save
Golden-brown Old-School Green Bean Casserole topped with crispy fried onions, ready to be served. | fireandbites.com

A nostalgic, creamy side dish featuring tender green beans, savory mushrooms, and crispy fried onions—this casserole is a classic for holiday feasts and family dinners. Each bite brings back memories of festive gatherings and comforting flavors.

The very first time I made this old-school green bean casserole, the aroma instantly transported me back to my grandmother's kitchen during Thanksgiving. Watching everyone take a scoop and smile is still one of my favorite holiday moments.

Ingredients

  • Fresh green beans: 900 g (2 lb), trimmed and cut into 5 cm (2-inch) pieces, or use 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: ½ tsp (optional)
  • Crispy fried onions: 150 g (1½ cups), store-bought or homemade

Instructions

Preheat the oven:
Set oven to 180°C (350°F).
Blanch green beans:
Boil salted water, add green beans, cook for 5 minutes, drain and rinse under cold water. Set aside.
Prepare mushrooms and aromatics:
Melt butter in a large skillet over medium heat. Add mushrooms, cook 5-6 minutes until browned. Add onion and garlic, cook 2-3 minutes until softened.
Make the sauce:
Stir in flour, cook 1 minute. Gradually whisk in milk, cream, and broth. Simmer 5 minutes until thickened. Season with salt, pepper, and nutmeg.
Combine beans and sauce:
Add green beans to skillet, toss to coat in sauce.
Assemble casserole:
Transfer mixture to 2-liter (2-quart) baking dish. Sprinkle half the fried onions over top.
Bake:
Bake 25 minutes until bubbling. Remove from oven, top with remaining onions, bake 5-7 minutes more until golden and crisp.
Cool and serve:
Let casserole cool for 5 minutes before serving.
A creamy, comforting pan of Old-School Green Bean Casserole, a classic holiday side dish. Save
A creamy, comforting pan of Old-School Green Bean Casserole, a classic holiday side dish. | fireandbites.com

When my cousins come over during holidays, we always end up reminiscing about our shared love for green bean casserole. It is the one dish that makes everyone gather around the table just a bit quicker!

Allergen Information

Contains milk (dairy), wheat (gluten in flour and fried onions), and possibly soy (in store-bought fried onions). Always verify store-bought ingredient labels for allergens.

Required Tools

Large pot, colander, large skillet, whisk, 2-liter (2-quart) baking dish, oven.

Nutritional Information

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

Bubbling Old-School Green Bean Casserole, with visible tender green beans and a crispy onion topping. Save
Bubbling Old-School Green Bean Casserole, with visible tender green beans and a crispy onion topping. | fireandbites.com

This casserole brings simple joy to every table. Enjoy creamy richness and crispy onions with every holiday meal.

Common Questions

How can I avoid soggy fried onions?

To keep fried onions crispy, add half before baking and the rest during the last few minutes of cooking to maintain their crunch.

Can frozen green beans be used instead of fresh?

Yes, frozen green beans work well if thawed and drained thoroughly before combining with the sauce.

What cheese options complement this dish?

Adding grated sharp cheddar or Gruyère can enrich the sauce with a deeper, savory flavor.

How do I thicken the creamy sauce without lumps?

Cook the flour briefly before gradually whisking in liquids to achieve a smooth, thickened sauce.

Can this dish be prepared ahead of time?

Yes, assemble up to step 6 and refrigerate for up to 24 hours; add onions and bake before serving.

Old-School Green Bean Casserole

Nostalgic creamy green beans with mushrooms and crispy fried onions, ideal for festive side dishes.

Setup Duration
15 min
Time at Heat
35 min
Complete Duration
50 min
Created by Logan Hayes

Recipe Type One-Pot Comfort Meals

Skill Level Easy

Cultural Background American

Output 6 Portion Count

Special Diet Info Meat-Free

What You'll Need

Vegetables

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

Sauce Base

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

Topping

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

Method Steps

Phase 01

Preheat oven: Set the 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-crisp and vibrant green; drain and rinse immediately under cold water to halt cooking.

Phase 03

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

Phase 04

Prepare sauce: Sprinkle in flour and stir constantly for 1 minute. Gradually whisk in milk, cream, and vegetable broth. Simmer until sauce thickens, approximately 5 minutes. Season with salt, pepper, and optional nutmeg.

Phase 05

Combine green beans with sauce: Add drained green beans to the skillet and fold them into the sauce until evenly coated.

Phase 06

Assemble and top: Transfer the mixture into a 2-quart baking dish. Evenly sprinkle half of the crispy fried onions over the top.

Phase 07

Bake initial layer: Place the dish in the oven and bake for 25 minutes until bubbling.

Phase 08

Add remaining topping and finish baking: Remove from oven, evenly distribute the remaining fried onions, and bake for an additional 5 to 7 minutes until the topping is golden and crisp.

Phase 09

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

Kitchen Tools Needed

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

Allergy Details

Always review ingredients individually for potential allergens and seek professional medical guidance if uncertain.
  • Contains milk (dairy), wheat (gluten), and possibly soy in store-bought fried onions.

Dietary Information (Single Portion)

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