This green bean casserole recipe is a delicious holiday side dish! It's made from scratch with fresh green beans and a creamy mushroom sauce.
Green bean casserole is always on my family’s Thanksgiving menu. We, like many folks, made the classic version with Campbell’s cream of mushroom soup, french fried onions, and canned green beans for years…until I set myself the task of making a homemade green bean casserole from scratch.
Let me introduce you to the results: this green bean casserole recipe. It stars fresh green beans, crispy onions, and a creamy mushroom sauce that blows the canned soup out of the water. Once I tried it, I couldn’t go back to the Campbell’s version, and I don’t think you’ll be able to either.
This green bean casserole recipe is fresh, colorful, and packed with savory flavor. Add it to your holiday table this year, and it’s guaranteed to be a hit.
Green Bean Casserole Ingredients
Here’s what you’ll need to make this recipe:
- Fresh green beans, of course! I like slender haricots verts best, but any type will do. In a pinch, frozen green beans are a fine substitute for fresh.
- Cremini mushrooms – For the homemade mushroom sauce. Swap in white button mushrooms if you prefer!
- Tamari or soy sauce – It brings out the mushrooms’ umami flavor.
- Garlic and thyme – They add fresh, earthy flavor to the sauce.
- Dijon mustard – For tangy flavor.
- Milk (any kind!) and Parmesan cheese – They give the mushroom sauce its creamy texture.
- All-purpose flour – It thickens the sauce.
- French fried onions – They create the casserole’s crispy, savory topping.
- Extra-virgin olive oil – For richness.
- And salt and pepper – To make all the flavors pop!
Find the complete recipe with measurements below.
Variation
Instead of using store-bought french fried onions, make crispy baked onions from scratch! It only takes about 30 minutes, and it’s so delicious. Find the full instructions in the recipe notes below.
How to Make Green Bean Casserole
You can find the complete recipe with measurements at the bottom of this post, but for now, here’s an overview of how it goes:
Start with the onions, if you’re making them from scratch. Tossed with flour, panko, olive oil, and salt, they take about 25 minutes to become crisp and golden brown in the oven.
Then, blanch the green beans until they’re crisp-tender and vibrant green. Drain and spread them on a kitchen towel to dry.
Next, make the sauce. Sauté the mushrooms, then add all the sauce ingredients except the Parmesan. Simmer until thickened, around 20 minutes. Finish the sauce with the cheese and black pepper.
Finally, assemble and bake! Enjoy hot from the oven.
Best Green Bean Casserole Recipe Tips
- Make sure your green beans are dry. No one likes a watery green bean casserole, so dry the green beans thoroughly after you blanch them!
- Watch the onions closely if you’re making them from scratch. They can quickly go from just right to burned, so make sure to keep an eye on them in the oven. I also like to rotate the pans every 10 minutes to help them cook evenly.
Can you make green bean casserole ahead of time?
Yes! You can make this casserole up to a day in advance. Here’s how:
- Blanch the green beans.
- Make the mushroom cream sauce.
- Layer the sauce and green beans in the casserole dish. Cover tightly and store in the refrigerator until just before serving.
- If you’re making the onions from scratch, store them at room temperature for up to 1 day.
- When you’re ready to bake, uncover the casserole and add the onion topping. Bake according to the recipe.
Storage
This recipe is best on the day it’s made, but leftovers keep well for up to 2 days. Store them in an airtight container in the fridge, and reheat in the microwave or a 350°F oven.
More Favorite Thanksgiving Recipes
If you love this recipe, try one of these Thanksgiving side dishes next:
- Best Stuffing
- Mashed Potatoes
- Sweet Potato Casserole
- Cranberry Sauce
- Roasted Brussels Sprouts
- Or any of these 50 Thanksgiving Side Dishes!
Green Bean Casserole
Ingredients
- 1½ pounds green beans, trimmed and halved
- 2 tablespoons extra-virgin olive oil
- 16 ounces cremini mushrooms, sliced
- 2 tablespoons tamari
- 4 garlic cloves, minced
- 2 tablespoons fresh thyme leaves
- ¼ cup all-purpose flour
- 3 cups milk, any kind
- 1½ teaspoons Dijon mustard
- ½ cup grated Parmesan cheese, plus more for sprinkling
- ¼ teaspoon freshly ground black pepper
- 1½ cups french fried onions, or homemade Crispy Baked Onions (see recipe notes)
Instructions
- Preheat the oven to 400°F. Lightly grease a 9x13-inch baking dish.
- Bring a large pot of salted water to a boil and set a large bowl of ice water nearby. Drop the green beans into the boiling water and blanch for 4 minutes. Immediately transfer to the ice water to stop the cooking process. Drain and transfer to a towel to dry.
- Heat the olive oil in a large skillet over medium heat. Add the mushrooms and cook until soft, 8 to 10 minutes. Stir in the tamari, garlic, and thyme. Sprinkle the flour over the mushrooms and stir again. Add the milk and mustard and stir to combine. Simmer until thickened, whisking often, 15 to 20 minutes. Stir in the Parmesan cheese and pepper.
- Spread ⅓ of the sauce at the bottom of the baking dish. Spread the green beans evenly on top, then top with the remaining sauce. Sprinkle on the onions and bake, covered, for 10 minutes. Uncover and bake for 10 more minutes. If the onions start to brown too much, cover the dish for the remainder of the baking time. Garnish with sprinkles of Parmesan, if desired. Serve hot.
Notes
Hi! What would you recommend if using frozen beans here?
I’ve always enjoyed the old-school green bean casserole of my youth, but wanted a bit of an upgrade. This one hit the mark, and was probably the most popular dish on my (Canadian) Thanksgiving table this year. It had a lighter feel, but lots of delicious mushroomy cheesy creamy flavor. And that onion topping….Do Not skip that part for a store-bought version. This recipe goes into the annual rotation.
I’m so glad you loved it, Tim!
Made this last night and it was delicious. Those Crispy Baked Onions are heavenly. Going to double those next time for snacking. The flavors were blended beautifully and with the home grown snap beans, what’s not to like??? We don’t eat Parm, so I subbed nutritional yeast, 1/1, and it was delicious. Will definitely make again and so glad we have leftovers for today. Thanks for this healthier version of creamy baked green/yellow beans.
I’m so glad you enjoyed the recipe, Paula!
I’m hoping to make this tomorrow for a New Years Eve dinner with family. Will oat milk thicken as nicely as regular milk? My family is dairy-free but our extended family is not. I really want it to be delicious but will sacrifice getting to eat it if regular milk is the way to go.
Hi Denise, I’ve successfully made it with almond milk, but we haven’t tried it without the cheese.
Thank you, Jeanine! I’m making it now and I’m a little nervous but your reply gave me a boost of confidence! Happy new year!
I substituted with oat milk, gluten-free AP flour, and (in the crispy onions) gluten-free panko bread crumbs. It thickened beautifully and was so delicious! I did keep the parmesan in but I think it would also be yummy without for completely dairy-free. Only compliments from everyone at dinner! Thank you, Jeanine!
I’m so glad it was a hit, Denise!
Excellent recipe, thank you for sharing it. I will definitely be making it again. I tripled it and served it to 22 people. Everyone enjoyed it. I highly recommend using fresh herbs.
Hi Tracey, I’m so glad it was such a hit!
I made this recipe for tonight’s Thanksgiving! It smells great so far! I think it’ll be a hot with all of its fresh ingredients. Thank you for this recipe!!
Made this for thanksgiving and it turned out really well! Not a fan of green bean casserole, but since was made using fresh ingredients from scratch, I was impressed with the results.
can soy sauce be used in place of tamari?
yep!
Amazing. Thank you for making this from scratch without canned soup and those fake weird onions.
Ha ha, I hope you enjoy it 🙂
Do you think nutritional yeast could be used instead of the cheese to punch up the mushroom sauce?
I think it could work – I’d probably start with 1 tablespoon.
Hi!
I am planning to make this for Thanksgiving this year but we are traveling so need to make ahead. Can I prepare as you mention above as if I was going to refrigerate, but instead freeze it and then bake it on Thanksgiving? Any suggestions would be helpful.
Thank you!
Hi Elizabeth, I haven’t tried freezing it – I’m not sure if the sauce mixture would get too clumpy.
We are dairy/gluten free and I wondered if I could use a mix of coconut milk/chicken stock for the milk? I know there are other types of milk, however I have digestive issues with all of them.
Absolutely loved this recipe. This was my second time making green bean casserole, first time using this recipe. It was such a hit! So much better than canned version. I made the sauce the night before and it took no time to assemble it the next day.
Hello,
I tried making this but there is so much milk left over. From your pictures it looks like the milk is fully absorbed. Any suggestion where I went wrong?
Hi Megan, it sounds like it could cook longer if it hasn’t thickened enough.