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!
need it to be NUT-free; don’t mind dairy
I would use gluten-free flour in place of oat flour (because I have it). Can you recommend a substitute (heavy cream perhaps) for the cashew mixture?
Hey Debbie, I’m not sure because I haven’t tried it myself, but I think heavy cream or half and half should work just fine!
Delicious. Happy to have vegan and healthy options for Thanksgiving. Gave the recipe to friends as well.
WOO! I am so glad that you are loving this recipe, Fran. Thank you so much for sharing this with your friends and for your review + star rating, it means so much to me.
What do you think about swapping the green beans for broccoli? I don’t love green beans but I love broccoli!
This is a very interesting idea, Ashlee! I haven’t tried broccoli in this recipe so I am not sure how it would work out. If you do give this a try, I’d love to know how it works out for you!
Being British I have never heard of this dish so I decided to have a go and make it. I was not disappointed not one bit. Absolutely Dlish with a capital D. Will be making again and again.
Ah yay! This makes me so happy to hear, Janet! Thanks so much for trying this recipe out and coming back to leave a review. I really appreciate it!
Update- I made the dish the night before and topped it with the onions once we got to our in-laws. This was by far the best dish on the table!! I loved it and the rest of the family did too! Such a yummy dish. I will be making this one again very soon! Thank you!
Ah yay!! So pumped to hear this green bean casserole was a hit, Courtney!! Thanks so much for the review. It means so much to me!
Hi! Can this be made the day before? Any suggestions on how to make it sheas and still have fresh taste?
Yes! I’m doing that this year! Going to prep everything and store the green beans casserole and the onions in the fridge overnight (separately) and then I’ll add the onions on top before baking tomorrow!
What do you think about swapping the green beans for broccoli? I don’t love green beans but I love broccoli!
Hello! This is the dish I will be bringing to thanksgiving this year. We will be traveling a few hours and I will be prepping it ahead of time. How do you suggest I do the onions so they will stay crispy? Put them in a paper bag or something? Thank you for the great recipe and Happy Thanksgiving!
Hi Courtney! I think that’s a great idea. I’m making it for Thanksgiving this year too and I’m going to store the onions separately.