Save to Pinterest 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 my grandma making this casserole every Thanksgiving. The aroma of mushrooms and onions gently cooking always signaled the start of the festive meal, and now I make sure it graces our table each year too.
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)
- Butter: 2 tbsp unsalted
- Mushrooms: 250 g (9 oz) cremini or button, 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)
- Vegetable broth: 120 ml (½ cup) low-sodium
- 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.
- Sautée 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 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 beans and sauce:
- 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.
- Rest:
- Let cool for 5 minutes before serving.
Save to Pinterest This casserole has become our go-to side dish for Christmas dinner, and the whole family insists on extra crispy onions every year.
Make It Your Own
Add 50 g of grated sharp cheddar or Gruyère to the creamy sauce for a richer twist. Try a splash of Worcestershire sauce for deeper flavor.
Serving Suggestions
Green bean casserole pairs perfectly with roast turkey or chicken, but it's also great alongside vegetarian mains at Sunday suppers.
Storing & Leftovers
Store leftovers in the fridge for up to 3 days. Reheat gently to maintain the creamy texture—add extra fried onions just before serving.
Save to Pinterest A scoop of this creamy, crunchy casserole is a true taste of tradition. Enjoy every comforting bite at your next gathering.
Answers to Recipe Questions
- → How do you keep green beans tender but crisp?
Blanch the green beans in boiling salted water for about 5 minutes, then rinse immediately under cold water to stop cooking and preserve color and texture.
- → What mushrooms work best for the sauce?
Cremini or button mushrooms are ideal as they offer a mild, earthy flavor that complements the creamy sauce.
- → Can this dish be prepared in advance?
Yes, you can assemble it up to the baking step, refrigerate for up to 24 hours, and add the crispy onions before baking.
- → What gives the sauce its creamy texture?
A combination of whole milk, heavy cream, butter, and flour creates a rich, velvety sauce that coats the green beans evenly.
- → How should the crispy fried onions be added?
Sprinkle half the onions before baking and the rest afterward for a golden, crunchy topping.