Old-School Green Bean Classic

Featured in: Seasonal Soul Recipes

This comforting side features fresh green beans lightly cooked and coated in a rich, savory sauce made from sautéed mushrooms, onions, and garlic. The sauce is thickened with flour and enriched with milk, cream, and vegetable broth, then baked to bubbly perfection before being topped with crispy fried onions for texture. Ideal for holiday dinners and easy to prepare ahead.

Updated on Sun, 09 Nov 2025 15:44:00 GMT
Creamy old-school green bean casserole topped with crispy onions for holiday dinners.  Save to Pinterest
Creamy old-school green bean casserole topped with crispy onions for holiday dinners. | lovelyserena.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 recipe reminds me of cozy family dinners where everyone looked forward to this comforting side dish on the table.

Ingredients

  • Vegetables: 900 g (2 lb) fresh green beans, trimmed and cut into 5 cm (2-inch) pieces (or substitute with 900 g frozen cut green beans, thawed and drained)
  • Sauce Base: 2 tbsp unsalted butter, 250 g (9 oz) cremini or button mushrooms, sliced, 1 small yellow onion, finely chopped, 2 garlic cloves, minced, 2 tbsp all-purpose flour, 240 ml (1 cup) whole milk, 120 ml (½ cup) heavy cream, 120 ml (½ cup) low-sodium vegetable broth, 1 tsp salt, ½ tsp black pepper, ½ tsp ground nutmeg (optional)
  • Topping: 150 g (1½ cups) crispy fried onions (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.
Cook Mushrooms and Aromatics:
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:
Add the drained green beans to the skillet and toss to coat evenly in the sauce.
Assemble Casserole:
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.
Cool and Serve:
Let cool for 5 minutes before serving.
Nostalgic old-school green bean casserole, featuring vibrant beans in savory mushroom sauce.  Save to Pinterest
Nostalgic old-school green bean casserole, featuring vibrant beans in savory mushroom sauce. | lovelyserena.com

Sharing this casserole at family gatherings always brings back warm memories and smiles around the table.

Nutritional Information

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

Allergen Information

Contains milk (dairy), wheat (gluten in flour and fried onions), and possibly soy (in store-bought fried onions). Always double-check labels before use.

Required Tools

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

Delicious old-school green bean casserole with crunchy onions, perfect for family feasts. Save to Pinterest
Delicious old-school green bean casserole with crunchy onions, perfect for family feasts. | lovelyserena.com

This classic green bean casserole is a warm and inviting addition to any holiday meal highlighting simplicity and flavorful comfort.

Ask About This Recipe

Can frozen green beans be used?

Yes, thawed and drained frozen green beans work well, offering convenience without compromising texture.

How can I make the sauce thicker?

Ensure to cook the flour briefly before adding liquids, then simmer the sauce until it thickens to a creamy consistency.

What can enhance the flavor?

Adding grated sharp cheddar or Gruyère cheese to the sauce provides extra richness and depth.

How to keep fried onions crispy?

Add the crispy onions halfway through baking and again near the end to maintain their crunch and golden color.

Is this suitable for vegetarians?

Yes, the dish uses vegetable broth and does not include meat, making it vegetarian-friendly.

Old-School Green Bean Classic

Creamy green beans with mushrooms and crispy onions, perfect for festive family gatherings.

Prep Duration
15 minutes
Cook Duration
35 minutes
Overall Time
50 minutes
Created by Serena Moore


Skill Level Easy

Cuisine American

Makes 6 Portions

Dietary Details No Meat

What You Need

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)

How To Make It

Step 01

Preheat oven: Preheat the oven to 350°F.

Step 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 and bright green. Drain and rinse under cold water to stop cooking. Set aside.

Step 03

Cook mushrooms and aromatics: Melt butter in a large skillet over medium heat. Add mushrooms and cook for 5-6 minutes until tender and browned. Add onion and garlic; cook 2-3 minutes until softened.

Step 04

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

Step 05

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

Step 06

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

Step 07

Bake with topping: Bake for 25 minutes until bubbly. Remove from oven, add remaining fried onions on top, and bake an additional 5-7 minutes until golden and crisp.

Step 08

Rest before serving: Let the dish rest for 5 minutes before serving.

Tools You'll Need

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

Allergy Details

Review ingredients for allergens and speak to your healthcare provider if you have concerns.
  • Contains milk (dairy), wheat (gluten in flour and fried onions), and possibly soy (in store-bought fried onions).

Nutrition per Portion

Details are for reference and aren't a substitute for expert medical guidance.
  • Energy: 265
  • Lipids: 15 g
  • Carbohydrates: 25 g
  • Proteins: 6 g