Healthy Green Bean Casserole
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Add as Google Trusted SourceThis healthy green bean casserole combines fresh green beans, creamy mushroom cashew sauce and crispy baked onions. A dairy-free Thanksgiving favorite made without canned soup!
Growing up, green bean casserole was at every holiday meal, and it’s still one of the sides I look forward to most. Give me that creamy mushroom sauce and crispy onion topping alongside my healthy sweet potato casserole, and I’m happy!
For this version, I use fresh green beans and make the mushroom sauce from scratch with cashews blended into a smooth cream. That’s what gives the filling its richness without any dairy or canned soup. And of course, I couldn’t skip the crispy onions! They bake in the oven while I work on the filling, so you still get that golden, crunchy topping in every scoop.
Table of contents
“This recipe is a 12/10! Seriously good. This is probably the best green bean dish I have ever had, so the fact that it is healthy is just an added bonus. This is going to be a Thanksgiving staple from here on out. Just make it. You will not be disappointed”
Why I Love This Green Bean Casserole
- Creamy without the dairy: Blended cashews give the mushroom sauce a rich, creamy texture without heavy cream or cheese.
- Homemade crispy onions: Thinly sliced onions bake with a coating of oat flour and panko for that crunchy topping I always want an extra spoonful of.
- A head start on Thanksgiving: You can assemble the casserole the night before and keep the onions separate until baking. One less thing to tackle while you’re making wild rice stuffing and the rest of your sides!
Ingredients Needed
- yellow onions – thinly sliced onions become the crispy baked topping. Try to keep the slices an even thickness so they cook at the same rate.
- oat flour and panko breadcrumbs – coat the onions for a crisp exterior. You’ll also use oat flour to thicken the mushroom sauce.
- raw cashews – use raw, unsalted cashews for a mild, creamy sauce. Soaking softens them so they blend more smoothly.
- unsweetened almond milk – helps blend the cashews into a pourable cream. Make sure it’s unflavored, too. Vanilla almond milk isn’t what we’re going for here!
- fresh green beans – trim the ends and cut the beans in half so they’re easier to scoop and eat.
- vegan butter – for sautéing the mushrooms and adding richness to the filling.
- baby bella mushrooms – give the sauce its savory mushroom flavor. These are also labeled cremini or baby portobello mushrooms.
- garlic – fresh minced garlic adds another layer of savory flavor.
- vegetable broth – helps bring the mushroom sauce together. I like low-sodium broth so there’s more control over the seasoning.
- tamari or soy sauce – a small splash deepens the savory flavor of the mushrooms.
Find the full ingredient list with measurements in the recipe card below.
Substitutions
- Use a different milk: Unsweetened, unflavored oat or soy milk can replace the almond milk. Regular dairy milk works too if you don’t need the casserole to be vegan.
- Make it gluten-free: Use certified gluten-free oat flour, gluten-free panko and gluten-free tamari instead of regular soy sauce.
- Swap the butter: Regular butter works in place of vegan butter if dairy isn’t a concern.
How to Make Healthy Green Bean Casserole
Step 1: Add cashews to a bowl and allow them to soak for at least 30 minutes.
Step 2: Combine onions with the Panko bread crumb mixture and bake for about 25 minutes.
Step 3: Boil the green beans for 5 minutes, then transfer to an ice bath to stop the cooking. Drain well.
Step 4: Blend soaked cashews with almond milk.
Step 5: Cook mushrooms for a few minutes, then add the cashew cream.
Step 6: Combine the sauce, green beans and some of the crispy onions. Transfer to a baking dish, top with the remaining onions and bake until bubbly and hot throughout.
Brittany’s Tips
- Watch the onions, not just the clock: Thin slices can brown quickly, especially around the edges of the pan. Check them when you toss and remove any browned pieces early so they don’t burn while the rest finish.
- Give the beans a taste: Before draining the boiling water, taste a bean. It should be crisp-tender, with a little bite but no raw crunch. If you prefer softer beans, give them another minute or two before transferring to the ice bath.
- Drain those beans well: After the ice bath, drain thoroughly and pat away excess water with a clean kitchen towel. You worked on that creamy mushroom sauce, and extra water clinging to the beans will only thin it out!
What to Serve with Green Bean Casserole
This is the kind of side I want next to all the Thanksgiving classics! Serve it with my air fryer turkey breast, mashed sweet potatoes and a spoonful of cranberry sauce for a little tartness alongside the creamy casserole.
For a plant-based holiday dinner, pair it with my lentil loaf. The maple glaze and savory mushroom sauce are such a good combination.
And of course, don’t forget about dessert! Check out my collection of healthy Thanksgiving desserts to find the perfect sweet treat to bring to the holiday table.
How to Make Green Bean Casserole Ahead of Time
Want one less dish to prep on Thanksgiving morning? Assemble the green beans and mushroom sauce in your baking dish the day before, then cover and refrigerate. Store the baked onions separately in an airtight container in the fridge to keep them from soaking up the sauce.
When you’re ready to bake, add the onions and follow the recipe directions. The chilled casserole may need extra time, so check that the center is hot and the sauce is bubbling before serving. If the onions brown before the filling is heated through, loosely cover the dish with foil.
How to Store Green Bean Casserole
- Storage: Store leftovers in an airtight container in the refrigerator for up to 4 days.
- Reheating: Warm individual portions in the microwave, or reheat the casserole in a 350°F oven until hot throughout. Loosely cover with foil if the onions start getting too dark.
- Freezing: Freeze the unbaked casserole without the onion topping for up to 2 months. Thaw overnight in the refrigerator, then add the topping before baking. The green beans will be softer after freezing, so I’d choose the overnight refrigerator option when prepping for Thanksgiving.
Frequently Asked Questions
Yes, but expect a softer texture. Drain and rinse them well, then skip the blanching and ice bath since canned beans are already cooked. Add them directly to the mushroom sauce when assembling the casserole.
The cashews may need more soaking time or a little longer in the blender. They should be soft enough to blend easily. A high-powered blender works best, and stopping to scrape down the sides helps catch any little pieces. Blend until completely smooth before adding the cream to the mushrooms.
The cashews give this sauce its creamy texture, so leaving them out will change the recipe. I haven’t tested a cashew-free version and don’t have a reliable substitute to recommend yet. If you’re looking for a simpler green bean side, try my green beans almondine and omit the almonds if needed.
More Holiday Side Dishes
If you enjoyed this recipe, please consider leaving a ⭐ star rating and let me know how it went in the 📝 comments below.
Healthy Green Bean Casserole
Ingredients
Crispy Baked Onions
Green Beans and Sauce
- ½ cup raw, unsalted cashews, soaked
- 1 cup unsweetened almond milk, or milk of choice
- 24 oz fresh green beans, rinsed, trimmed and halved
- 2 Tablespoons vegan butter
- 12 oz baby portobello mushrooms, trimmed and cut into 1/2-inch pieces
- 1 teaspoon sea salt
- 1 teaspoon ground pepper
- 3 cloves garlic, minced
- ¼ teaspoon ground nutmeg
- 2 Tablespoons oat flour
- 1 cup vegetable broth
- 1 teaspoon low-sodium tamari, or soy sauce
Instructions
- Add cashews to a bowl with water for soaking. Let soak for at least 30 minutes.½ cup raw, unsalted cashews
- Preheat the oven to 475°F.
- Combine the onions, oat flour, panko and salt in a large mixing bowl and toss to combine. Coat a sheet pan with nonstick cooking spray and evenly spread the onions on the pan. Place the pan on the middle rack of the oven and bake until golden brown, approximately 25 minutes, tossing every 10 minutes. Once done, remove from the oven and set aside until ready to use. Reduce oven temperature to 375°F.2 medium onions, ¼ cup oat flour, 2 tablespoons panko bread crumbs, 1 teaspoon sea salt, Nonstick cooking spray
- While the onions are cooking, prepare your green bean mixture.
- Bring a large pot of water to a boil. Add the beans and blanch for 5 minutes. Drain in a colander and immediately plunge the beans into a large bowl of ice water to stop the cooking. Drain and set aside in large bowl.24 oz fresh green beans
- Drain cashews and add to a blender with almond milk. Blend until smooth and creamy and set aside.1 cup unsweetened almond milk
- Melt the butter in a large skillet over medium-high heat. Add the mushrooms, salt and pepper and cook, stirring occasionally for 4 to 5 minutes. Add the garlic and nutmeg and continue to cook for another 1 to 2 minutes. Sprinkle the oat flour over the mixture and stir to combine. Cook for 1 minute. Add the broth and tamari, simmer for 1 minute.2 Tablespoons vegan butter, 12 oz baby portobello mushrooms, 1 teaspoon sea salt, 1 teaspoon ground pepper, 3 cloves garlic, ¼ teaspoon ground nutmeg, 1 cup vegetable broth, 1 teaspoon low-sodium tamari, 2 Tablespoons oat flour
- Decrease the heat to medium-low and add the cashew cream. Cook until the mixture thickens, stirring occasionally, approximately 6 to 8 minutes.
- Remove from the heat and pour sauce into a large bowl with the green beans and ½ cup of the crispy baked onions. Place green bean mixture into a 8×8 baking dish and top with the remaining crispy baked onions. Place into the oven and bake until bubbly and warm throughout, approximately 15-20 minutes. Remove and serve immediately.
Video
Notes
- Make ahead: Prepare the casserole the day before, reserving the baked onions separately. Cover and refrigerate both. Add the onions before baking and allow extra baking time as needed, until hot throughout.
- Gluten-free: Use certified gluten-free oat flour, gluten-free panko and gluten-free tamari.
- Storage: Refrigerate leftovers in an airtight container for up to 4 days. Reheat individual portions in the microwave or warm in a 350°F oven until heated through.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Like This Recipe? Rate & Comment Below!
Hey Brittany. Happy thanksgiving! Can this dish be made ahead waiting prep & add the onions prior to baking? TIA!
Yes! I’m doing that same thing this year! Going to prep everything and store the green beans casserole and the onions in the fridge overnight but separately and then I’ll add the onions before baking tomorrow!
I made this last year! Loved it , question what kind of onion do you purchase to make fried onions? White, Vidalia or sweet onion?
I typically buy the bagged yellow onions. They’re usually called sweet yellow onions.
BY FAR the best green bean casserole ever. In fact, I don’t usually like green bean casserole, but this one was divine. Willingly eating the leftovers for lunch right now!
Ah yay! This makes me so happy to hear. Thanks so much for trying it out and I really appreciate the review!
This recipe is a 12/10! Seriously good. This is probably the best green bean dish I have ever had, so the fact that it is healthy is just an added bonus. This is going to be a Thanksgiving staple from here on out. Just make it. You will not be disappointed.
Ahh yay, that makes me so happy to hear! I’m pumped you hear you loved this recipe, Sandie. Thanks for making it and for coming back to leave a comment + star rating. I so appreciate it!
I made this recipe for my family‘s Thanksgiving and while it was a lot of extra work, it was all definitely worth it! The one comment my family had is that they would have preferred canned green beans which I think would be good as well. I definitely enjoyed it and thought it was a very unique and flavorful recipe. I always love testing out Brittany‘s recipes..thank you for sharing!
I’m glad you enjoyed this recipe, Mikki! Thanks for making it – it means the world to me. 🙂
I made this for my first vegan thanksgiving and I LOVED it! Sad to say my thanksgiving guests did not appreciate it as much as I did. I guess they were used to more “soggy” beans from the can (which I think is gross) but to each their own! More for me!! Only mishap was that I burnt the first round of onions following your instructions. I ended up having to do another batch with my oven turned down about 50 degrees. Maybe its my oven! Thanks for this amazing recipe, it made my day!
I’m glad you enjoyed this casserole, Jessi! And I’m glad the second round of onions worked for you. Sorry the first round burned, it definitely could have been because your oven got hotter and maybe they just needed less time or a lower temp.
This was a huge hit at Thanksgiving, loved it. However, it had a little kick and trying to figure out what it is? I wouldn’t have thought nutmeg would make it spicy?
So glad this casserole was a hit at Thanksgiving! It definitely shouldn’t have been spicy. Nutmeg adds a warm, woody flavor, with hints of clove, but it shouldn’t necessarily be spicy especially with just 1/4 tsp.
This recipe is great, we used cup for cup gluten free flour as a sub and it came out perfectly. Thank you!
So glad this casserole turned out for you, Samantha! Thanks for making it and for coming back to leave a review. I so appreciate it!
Can I make this the day before and add crispy onion toppings before I bake it?
Hey Jullian, Sorry I’m just seeing this comment. Did you end up making this casserole? How’d it turn out?!
This is so delicious! I have always avoided this on the Thanksgiving table because it was always presented to me with canned everything and did not appeal. THIS, however, is AMAZING. It is Thanksgiving Eve and I have parboiled the green beans and I made the sauce. I will make the onions and assemble and bake tomorrow. But this sauce is so so so tasty! And the sauce is what counts so that is why i have already given this 5 stars. Seriously. How is this vegan?! Thank you, Brittany! Your recipes have been making my transition to whole food plant based eating easier! And your treats that aren’t necessarily whole foods are great in that they check the boxes for being vegan and healthier and tasty!
Ahh yay, this makes me so happy to hear, Katie!! I’m so glad to hear that you tried this recipe. Definitely come back and let me know what you think of it once you have it tomorrow. 🙂 I really appreciate the sweet review, it means the world to me!!