Old-School Green Bean Casserole

Featured in: Family Sharing Plates

This nostalgic green bean casserole combines tender green beans with a rich sauce made from sautéed mushrooms, onions, and creamy milk and cream. Topped with crispy fried onions, it bakes to golden perfection with a satisfying crunch. Ideal for holiday feasts or family dinners, this side dish offers a balance of texture and flavor that is comforting and full of warmth.

The preparation involves briefly cooking the green beans, simmering the sauce until thickened, coating the beans thoroughly, and baking the casserole twice to achieve both bubbling warmth and a crisp topping. Optional additions like sharp cheddar or Gruyère enhance the depth of flavor. This dish pairs beautifully with roasted poultry and suits vegetarian diets.

Updated on Sun, 09 Nov 2025 13:47:00 GMT
Creamy old-school green bean casserole topped with crispy fried onions and mushrooms.  Save
Creamy old-school green bean casserole topped with crispy fried onions and mushrooms. | cookinget.com

Old-School Green Bean Casserole is a nostalgic, creamy side dish featuring tender green beans, savory mushrooms, and crispy fried onions. It's a classic addition to holiday feasts and memorable family dinners, sure to bring a comforting touch to your table.

This is the side dish I always looked forward to at family gatherings. Over the years, I perfected my own version, trading canned soup for a made-from-scratch sauce that still tastes just like childhood memories.

Ingredients

  • Fresh Green Beans: 900 g (2 lb) trimmed and cut into 5 cm (2-inch) pieces or 900 g frozen cut green beans, thawed and drained
  • Unsalted Butter: 2 tbsp, for sautéing
  • Cremini or Button Mushrooms: 250 g (9 oz) sliced
  • Yellow Onion: 1 small, finely chopped
  • Garlic Cloves: 2, minced
  • All-Purpose Flour: 2 tbsp, for thickening
  • 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 and Prepare:
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. 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 and cook for another 2-3 minutes until softened.
Make the 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 and Assemble:
Add the drained green beans to the skillet and toss to coat evenly in the sauce.
Transfer and 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.
Cool and Serve:
Let cool for 5 minutes before serving.
Classic old-school green bean casserole, perfect for holiday dinners and potlucks.  Save
Classic old-school green bean casserole, perfect for holiday dinners and potlucks. | cookinget.com

I always make this with my kids on Thanksgiving morning. Everyone helps trim beans and sneak a few crispy onions before the casserole goes into the oven—it's become our favorite holiday tradition.

Make-Ahead and Storage

Assemble the casserole up to the baking step and refrigerate for up to 24 hours. When ready to serve, simply add the fried onions and bake as directed until golden and bubbling.

Flavor Variations

Stir in 50 g grated sharp cheddar or Gruyère cheese to the sauce for extra richness, or add a pinch of cayenne for a subtle kick. Use different mushrooms for a twist on classic flavor.

Serving Suggestions

This casserole pairs beautifully with roasted turkey or chicken, or even as a vegetarian main dish alongside mashed potatoes and cranberry sauce.

Delicious old-school green bean casserole with tender beans and savory creamy sauce. Save
Delicious old-school green bean casserole with tender beans and savory creamy sauce. | cookinget.com

This classic green bean casserole adds comfort to any meal. Make it once and you'll want to serve it at every family gathering.

Recipe FAQs

How do I prevent the green beans from becoming mushy?

Cook them briefly in boiling salted water until just tender and bright green, then rinse under cold water to stop cooking immediately.

Can I use frozen green beans instead of fresh?

Yes, thaw and drain frozen green beans thoroughly before using to maintain the right texture.

What is the purpose of the crispy fried onions?

They add a crunchy texture and savory contrast to the creamy, tender layers beneath.

How can I make the sauce richer in flavor?

Adding grated sharp cheddar or Gruyère cheese to the sauce will enhance its depth and creaminess.

Is this dish suitable for vegetarians?

Yes, it contains no meat and uses vegetable broth, making it suitable for vegetarian diets.

Can I prepare this dish ahead of time?

Assemble up to the step before baking, refrigerate for up to 24 hours, then add onions and bake before serving.

Old-School Green Bean Casserole

Classic creamy side with green beans, mushrooms, and crispy fried onions, perfect for festive gatherings.

Prep Duration
15 minutes
Time to Cook
35 minutes
Overall Time
50 minutes
Recipe by Sophie Daniels


Skill Difficulty Easy

Cuisine American

Output 6 Portion Count

Diet Preferences Vegetarian Option

What You'll 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)

Directions

Step 01

Preheat oven: Set the oven to 350°F (180°C) to preheat.

Step 02

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

Step 03

Sauté vegetables: Melt butter in a large skillet over medium heat. Add mushrooms and sauté for 5–6 minutes until tender and browned. Add onion and garlic, cooking 2–3 minutes until softened.

Step 04

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

Step 05

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

Step 06

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

Step 07

Bake with onions: Bake for 25 minutes until bubbly. Remove from oven, top with remaining onions, and bake 5–7 minutes more until golden and crisp.

Step 08

Rest and serve: Let the dish cool for 5 minutes before serving.

Essential Tools

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

Allergy Details

Review all ingredients for allergens. Ask a medical expert when uncertain.
  • Contains milk (dairy), wheat (gluten in flour and fried onions), and possible soy (in store-bought fried onions). Verify product labels.

Nutrition Facts (per portion)

These numbers offer reference only, not medical guidance.
  • Energy Value: 265
  • Fats: 15 g
  • Carbohydrates: 25 g
  • Proteins: 6 g