This green bean casserole recipe is an updated take on the classic 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, right alongside the mashed potatoes, stuffing, and cranberry sauce. We, like many folks, made the 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 baked onions, and a rich and 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 green bean casserole recipe:
- Fresh green beans, of course! I like haricots verts best here, but any fresh green beans will do. In a pinch, frozen green beans are a fine substitute.
- Cremini mushrooms – For the creamy 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, savory flavor to the sauce.
- Dijon mustard – It makes the sauce taste nice and tangy.
- Milk (any kind!) and Parmesan cheese – They give the mushroom sauce its creamy texture. The Parmesan adds rich, nutty flavor too!
- All-purpose flour – It thickens the mushroom sauce and helps the onions crisp up in the oven.
- Yellow onions – You’ll thinly slice them for the crispy onion topping.
- Panko breadcrumbs – They work with the flour to make the onions crispy.
- Extra-virgin olive oil – It adds richness to the sauce and helps the onions crisp up as they bake.
- And salt and pepper – To make all the flavors pop!
Find the complete recipe with measurements below.
How to Make Green Bean Casserole
This green bean casserole recipe has three components: the crispy onions, the green beans, and the mushroom sauce. 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. Thinly slice the onions and toss them with olive oil, flour, salt, and panko. Spread them in an even layer on two large baking sheets and roast until they’re golden brown and beginning to crisp up, tossing them every 10 minutes.
- Variation: Short on time? Streamline this recipe by using store-bought French fried onions instead of these crispy baked ones.
Then, blanch the green beans. Bring a large pot of salted water to a boil and add the green beans. Cook for 4 minutes, stirring occasionally, until the beans are crisp-tender and vibrant green. Drain them, and transfer them to a large bowl of ice water to stop the cooking process. After they’ve cooled, spread them on a kitchen towel to dry.
Next, make the sauce. Sauté the mushrooms until they’re soft, and stir in tamari, garlic, and thyme for flavor. Sprinkle in some flour, and add milk and Dijon mustard. Simmer until thickened, around 20 minutes. Then, stir in Parmesan cheese and black pepper.
Finally, assemble and bake! Cover the bottom of a greased baking dish with a thin layer of the sauce. Pile in the tender green beans, and spread the rest of the sauce on top. Sprinkle with the crispy onions, and bake, covered, for 10 minutes. Uncover the baking dish, and bake for 10 minutes more.
Enjoy!
Best Green Bean Casserole Recipe Tips
- Look for haricots verts. Any type of fresh green beans will work in this recipe, but we had the best results with thin haricots verts. They’re slimmer than regular green beans, which helps them integrate with the sauce and onion topping. Plus, they have a delicious snappy texture!
- Watch the onions as they cook, and rotate the pans. When you toss the onions every 10 minutes as they cook, rotate their baking sheets. This will help ensure even cooking—you don’t want one pan to burn before the other gets crispy! Watch them closely near the end of the cooking time, as they can quickly go from just right to burned.
- Or use store-bought French fried onions. Want to streamline this recipe? Replace the crispy baked onions with 1 1/2 cups French fried onions.
- Make sure your green beans are dry. No one likes a watery green bean casserole, so make sure to dry the green beans thoroughly after you blanch them!
Can you make green bean casserole ahead of time?
Yes! You can make this green bean casserole recipe up to a day in advance. Here’s how:
- Bake the crispy onions, and store them at room temperature.
- Blanch the green beans.
- Make the mushroom cream sauce.
- Assemble the casserole with the sauce and green beans. Cover tightly and store in the refrigerator until just before serving.
- When you’re ready to bake, uncover the casserole and add the crispy onions. Bake the casserole according to the recipe until it’s heated through.
Storage
This green bean casserole 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 green bean casserole recipe, try one of these Thanksgiving side dishes next:
- Best Stuffing
- Mashed Potatoes
- Sweet Potato Casserole
- Cranberry Sauce
- Butternut Squash Soup
- Roasted Acorn Squash
- 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. Drain, and immediately immerse in the ice water to stop the cooking process. Drain, and transfer to a towel to dry.
- Heat the olive oil in a large skillet, 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 into the baking dish. Layer with green beans and top with the remaining sauce. Sprinkle the onions on top and bake, covered, for 10 minutes. Uncover and bake 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
Made according to recipe. Was really really good. Only added a bit of apple cider vinegar and red pepper at the end. Really a nice change from traditional. Thank you.
I’m so glad you loved it!
Hi! Thanks for this great recipe! I’m planning on using my crockpot instead since my small oven will be busy with other dishes….how could I adapt for crockpot? Thanks!
Hi Elizabeth, I’m not sure, I think the mushroom sauce would work fine, but I would recommend baking it in a dish so that the onions get/stay crispy.
I’m planning to make this for Thanksgiving because it sounds like it will taste WAY better than the recipes using canned stuff and I just had a question about the instructions. It says to layer sauce, beans, sauce and I was wondering why you don’t mix the beans into the sauce and then put it all in the dish together and then top with the onions. I’m guessing that it melds together as it cooks, but is there a reason you don’t mix them together beforehand? I feel like you’d get more consistent bean/sauce melding if you did, but I didn’t want to mix them and mess it up if you’ve tried it and gotten better results layering them. I’m sure that presentation-wise, it looks better as written, but I’m not overly concerned about that since no matter what I do, it’s going to look better than the canned version!
Hi Susan, yes, between the sauce on the bottom and top of the green beans, it melds together. If you’d prefer to mix it together first, that would work too.
Can you assemble the night before and cook the next day? Thanks!
Hi Caroline, you can assemble the green beans and mushroom sauce in the baking dish the night before. I’d keep the crispy onions separate at room temperature until you’re ready to bake.
I can’t wait to try this casserole. Which size baking dish is best for these proportions?
Hi Christy, you can use a 9×13 baking dish.
My sister and niece are vegan. The rest of us love Parmesan. Is there a way substitute that will not have an overpowering taste of yeast?
Thank you!
Oops—Is there a way to substitute some other ingredient…
Nooch?
Do I have to use almond milk?
Hi Becca, you can use any milk.
Is there another vegan substitute you could use for the parmesan cheese, as that would help thicken the sauce as well. I might add some mushroom powder, and black salt for umami, but that won’t increase the thickness of the sauce.
Hi!
I’d love to make this for Canadian Thanksgiving and was wondering if this could be made 2 days in advance? We’re travelling and prefer to have it done ahead of time before leaving.
Cheers!
How many cans of cream of mushroom soup should I use – I have many in the pantry that I would like to use up.
Hi there, I know I’m a little late to the game with this recipe, but wondering if you have any suggestions for making it a vegetarian main dish casserole? (By adding protein and starch of some sort…)
Have always loved Green Bean Casserole, but haven’t made it in years because it’s just not Healthy. This recipe was a great find, and has found a permanent home in my recipe box. Thank you!
Hello! Could I sub gluten free flour and bread crumbs to make this a GF dish?
I did and it turned out great
OMG this was delicious!!! Everyone liked it at our Thanksgiving Celebration.
I changed Tamari for Coconut Aminos as we try not to use soy. I also used Almond Flour and Gluten Free Panko to make it Gluten Free. I decided to Omit the Parmesan Cheese as we are dairy free.
It was delicious!!!! Thank you!
Hi Jacky, I’m so glad this was such a hit! Thanks for coming back with your notes about making it gluten free – I’m happy to hear that it was so great with almond flour.
It’s supposed to be thick, not runny – it should be clumpy from the mushrooms, if it’s clumpy otherwise, try sprinkling in the flour slower, while whisking.
I’m having trouble with my onions. I’m following your recipe step by step, but no matter what I do they keep coming out burnt only after 20 minutes. Any suggestions on what I can do to get that golden brown?
Hi Lauren, I wonder if you’re slicing them thinner than I was. I’d try slicing them a tad thicker… if they’re still browning too soon, I’d just take them out early. Ovens can really vary and they’ll finish crisping on the final bake. Hope that helps!
I would try lowering the temp of the oven. Maybe your oven runs hot. One of my ovens does this and I have a hard time with cookies.
Can the whole dish, minus the crispy onions, be made a day in advance, stored in the fridge, and then baked off day of?
Yep, it can!
Hi – I am planning on making this ahead of time since I am traveling and don’t want it to get cold. My understanding is that I can premake everything, assemble it (minus the onions) and then when I get to my destination, I bake for 10 mins covered and 10 mins uncovered as if I was making it all at once? I don’t want to mess anything up! Thanks!
Hi Lauren, yes exactly – once you get to your destination, put the onions on top and bake it!
It was delicious and a huge hit at Thanksgiving dinner, thank you! The onions were burning after 25 minutes, but I was able to salvage most.
Do you use almond milk as a healthier alternative? Could I still use something like whole milk?
Hi Emily, I used it because it’s what I keep on hand. You could use whole milk!
great side dish, a lot of great ingredients that all meld together, thank you
We are a mushroom-free household. In recipes that have called for cream of mushroom soup, I’ve always substituted a different cream soup (celery, potato, even tomato when it wouldn’t be bizarre). Any suggestions for alternatives in this recipe?
Hi Janet, any of those subs would work in this recipe as the sauce component, if you prefer.
Any suggestion for substituting for the mushrooms and keeping the rest of the filling recipe? I would rather make something fresh rather than use a canned soup…
Hi Janet, mushrooms are the main ingredient of the sauce so I don’t have a substitution for them in this recipe.
I would try riced cauliflower browned in butter. Wouldn’t give the mushroom flavor, but I think it would fill in nicely.