Save A nostalgic, creamy side dish featuring tender green beans, savory mushrooms, and crispy fried onions—a classic for holiday feasts and family dinners.
I first made this casserole for Thanksgiving at my grandmother's house and it instantly became a family staple. It captures all the coziness of traditional holiday gatherings!
Ingredients
- Fresh green beans: 900 g (2 lb), trimmed and cut into 5 cm (2-inch) pieces (or substitute 900 g frozen 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 (1/2 cup)
- Low-sodium vegetable broth: 120 ml (1/2 cup)
- Salt: 1 tsp
- Black pepper: 1/2 tsp
- Ground nutmeg (optional): 1/2 tsp
- Crispy fried onions: 150 g (1 1/2 cups), store-bought or homemade
Instructions
- Preheat Oven:
- Preheat the oven to 180°C (350°F).
- Blanch 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. Set aside.
- Sauté 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 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:
- 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.
- Serve:
- Let cool for 5 minutes before serving.
Save My kids always ask for seconds of this casserole, especially when we gather for festive meals. It's become part of our holiday kitchen traditions.
Serving Suggestions
This casserole pairs beautifully with roast turkey, baked chicken, or as part of a vegetarian feast. Serve hot and watch it disappear fast!
Make-Ahead & Storage
Assemble up to a day ahead and bake when ready to serve. Leftovers keep, covered, in the refrigerator for up to 3 days.
Variations
For a cheesy twist, add grated sharp cheddar or Gruyère to the sauce. Swap mushrooms for caramelized shallots or try adding roasted red peppers for color.
Save Serve this classic alongside your favorite main dish and enjoy the nostalgia with every bite. Leftovers are just as delicious the next day!
Recipe FAQ
- → Can I use frozen green beans instead of fresh?
Yes, thawed and drained frozen green beans work well, making preparation quicker without sacrificing texture.
- → How do I get crispy fried onions on top?
Use store-bought fried onions or make your own by thinly slicing onions, coating them in flour, and frying until golden and crisp.
- → What can I add for extra richness?
Incorporate grated sharp cheddar or Gruyère cheese into the sauce for a richer, more indulgent flavor.
- → How to prevent the beans from overcooking?
Blanch the beans just until tender-crisp, then rinse under cold water to stop cooking and keep their bright green color.
- → Can this be prepared ahead of time?
Yes, assemble up to the baking step and refrigerate for up to 24 hours before adding the onions and baking.