Old-School Green Bean Casserole

Featured in: Family Dinners

This nostalgic dish features tender green beans simmered in a rich, creamy sauce crafted from mushrooms, garlic, and onions. The sauce is thickened with flour and balanced with seasoning, then baked with a crispy topping of golden fried onions. A comforting side perfect for holiday gatherings or family dinners, it brings a classic American flavor with a smooth texture and satisfying crunch.

Updated on Sat, 15 Nov 2025 11:50:00 GMT
Creamy Old-School Green Bean Casserole topped with crispy fried onions, a holiday dinner staple. Save
Creamy Old-School Green Bean Casserole topped with crispy fried onions, a holiday dinner staple. | griddleglory.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 this casserole gracing our holiday table every year. The creamy sauce and crispy onion topping were always crowd-pleasers, making leftovers a rare treat.

Ingredients

  • Fresh green beans: 900 g (2 lb), trimmed and cut into 5 cm (2-inch) pieces (or substitute with 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

Prep oven:
Preheat the oven to 180°C (350°F).
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 stop cooking. Set aside.
Cook vegetables:
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 for another 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 (if using).
Combine and transfer:
Add drained green beans to the skillet and toss to coat evenly.
Bake:
Transfer mixture to a 2-liter (2-quart) baking dish. Sprinkle half of the crispy fried onions on top. Bake for 25 minutes until bubbling.
Finish topping:
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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| griddleglory.com

Sharing green bean casserole around our table is a tradition that brings everyone together and sparks stories from years gone by.

Preparation and Cooking Time

It takes about 15 minutes to prep and 35 minutes to cook, so you'll have a finished casserole in under an hour.

Make-Ahead and Leftovers

You can assemble up to baking, refrigerate for up to 24 hours, then bake with onions before serving. Leftovers reheat well.

Nutritional Information

Each serving contains 265 calories, 15 g total fat, 25 g carbohydrates, and 6 g protein.

A warm baking dish of Old-School Green Bean Casserole, bubbly and golden, ready to serve. Save
A warm baking dish of Old-School Green Bean Casserole, bubbly and golden, ready to serve. | griddleglory.com

Green bean casserole is the heart of any nostalgic feast. Serve warm and enjoy each creamy, crunchy bite.

Cooking Questions

Can frozen green beans be used instead of fresh?

Yes, frozen green beans can be thawed and drained before cooking to achieve a similar texture.

What alternatives are there for crispy fried onions?

You can use store-bought fried onions or make them at home by frying thinly sliced onions until golden and crunchy.

How can the sauce be thickened properly?

Cooking flour with butter before adding liquids ensures a smooth, thickened sauce without lumps.

Is it possible to prepare this dish ahead of time?

Yes, assemble everything up to the baking step and refrigerate for up to 24 hours. Add topping and bake when ready.

What cheese options enhance the flavor?

Adding grated sharp cheddar or Gruyère to the sauce adds a rich, savory depth.

What dishes pair well with this green bean side?

This side complements roast turkey, chicken, or other hearty mains for holiday meals.

Old-School Green Bean Casserole

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

Prep duration
15 min
Cook duration
35 min
Complete duration
50 min
Created by Sarah Collins


Skill level Easy

Heritage American

Output 6 Portions

Nutrition specifications Meat-free

Components

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 black pepper
11 ½ teaspoon ground nutmeg (optional)

Topping

01 1½ cups crispy fried onions, store-bought or homemade

Directions

Phase 01

Preheat Oven: Set the oven temperature to 350°F.

Phase 02

Blanch Green Beans: Boil a large pot of salted water. Add green beans and cook for 5 minutes until tender-crisp and bright green. Drain and rinse under cold water to stop cooking. Set aside.

Phase 03

Sauté Vegetables: Melt butter in a large skillet over medium heat. Add mushrooms and cook for 5 to 6 minutes until browned and tender. Stir in onion and garlic, cooking an additional 2 to 3 minutes until softened.

Phase 04

Prepare Sauce: Sprinkle flour over vegetables and stir continuously for 1 minute. Gradually whisk in milk, cream, and vegetable broth. Simmer until thickened, approximately 5 minutes. Season with salt, pepper, and optional nutmeg.

Phase 05

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

Phase 06

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

Phase 07

Bake Initial Layer: Place dish in oven and bake for 25 minutes until sauce is bubbling.

Phase 08

Add Remaining Topping and Finish Baking: Remove from oven, distribute remaining fried onions on top, and bake an additional 5 to 7 minutes until topping is golden and crisp.

Phase 09

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

Necessary tools

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

Allergy details

Review each component for potential allergens and seek professional healthcare advice if you're uncertain.
  • Contains dairy from milk and cream.
  • Contains gluten in flour and fried onions.
  • Possible soy presence in store-bought fried onions.

Nutritional information (per portion)

These values are provided as a general guide only and aren't intended to replace professional medical guidance.
  • Energy: 265
  • Fats: 15 g
  • Carbohydrates: 25 g
  • Proteins: 6 g