Pin It A nostalgic, creamy side dish featuring tender green beans, savory mushrooms, and crispy fried onions—a classic for holiday feasts and family dinners.
This casserole is one of those essential dishes my family insists on every Thanksgiving. I learned to make it from my grandmother, and every bite brings back those festive memories.
Ingredients
- Fresh green beans: 900 g (2 lb), trimmed and cut into 5 cm (2-inch) pieces (or substitute with 900 g 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).
- 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 rinse under cold water. Set aside.
- Make Sauce Base:
- Melt butter in a large skillet over medium heat. Add mushrooms and cook for 5-6 minutes until tender and browned. Stir in chopped onion and garlic, cooking for 2-3 minutes until softened.
- Thicken Sauce:
- Add flour and stir constantly for 1 minute. Gradually whisk in milk, cream, and broth. Simmer until thickened, about 5 minutes. Season with salt, pepper, and nutmeg if using.
- Combine Beans & Sauce:
- Add drained green beans to the skillet and toss to coat in sauce.
- Assemble & Bake:
- Transfer mixture to a 2-liter (2-quart) baking dish. Sprinkle half the fried onions on top.
- Finish Baking:
- Bake for 25 minutes until bubbling. Remove, top with remaining onions, and bake for 5-7 minutes more until golden and crisp.
- Serve:
- Let cool for 5 minutes before serving.
Pin It 
Gathering around the holiday table and sharing this green bean casserole always brings my family together—it is the dish everyone reaches for first.
Required Tools
Large pot, colander, large skillet, whisk, 2-liter baking dish, oven
Allergen Information
Contains: Milk (dairy), Wheat (gluten in flour and fried onions), Soy (possible in store-bought fried onions). Always double-check packaged ingredients for allergens.
Nutritional Information
Per serving: 265 calories, 15 g total fat, 25 g carbohydrates, 6 g protein
Pin It 
Enjoy this creamy classic alongside roast turkey or chicken for the ultimate holiday spread. Leftovers reheat beautifully!
Recipe Questions & Answers
- → What type of green beans work best?
Fresh green beans trimmed and cut into two-inch pieces provide the best texture, but thawed frozen green beans can be used as a convenient alternative.
- → How can I make the sauce thicker?
Cooking the sauce base over medium heat after adding flour and slowly whisking in milk, cream, and broth until it simmers ensures it thickens properly.
- → Can I prepare this dish ahead of time?
Yes, you can assemble everything up to the baking step, refrigerate for up to 24 hours, then add the fried onions and bake when ready.
- → Are there any suggested flavor variations?
Adding sharp cheddar or Gruyère cheese to the sauce enhances richness and depth of flavor.
- → What is the purpose of the crispy fried onion topping?
It adds a crunchy texture contrast to the creamy vegetables and sauce, making each bite more interesting.
- → Is this dish suitable for vegetarians?
Yes, with vegetable broth and standard dairy ingredients, it fits vegetarian preferences.