Creamy Vegan Green Bean Casserole (From Scratch)
This vegan green bean casserole skips the canned soup and builds its own creamy, mushroom-free sauce from scratch. It’s the Thanksgiving classic, just plant-based and made with recognizable ingredients you can feel good about.
The green beans stay tender-crisp, the sauce is savory and rich, and the crispy onion topping is every bit as golden and crunchy as you remember. Make it ahead of time, and it holds up beautifully on a holiday table or a weeknight dinner.
Why This Vegan Green Bean Casserole Works
It tastes like the real deal. The sauce gets its body from blended cashews and a quick roux, so there’s no need for dairy or condensed soup. Nutritional yeast and a touch of soy sauce add that deep umami without overpowering the beans.
Every component delivers. Blanching the green beans keeps them bright and toothsome, not mushy. The baked casserole has a creamy interior and a crispy top that stays crunchy even after sitting out on the buffet.
The recipe is flexible. You can make the sauce a day in advance, use frozen beans in a pinch, or swap the crispy onions for a homemade gluten-free version. It plays nice with any main course.
Ingredients
- 1 lb fresh green beans, trimmed and halved: look for firm, slender beans that snap cleanly.
- 1 cup raw cashews: soaked in hot water for at least 15 minutes to soften.
- 1 cup vegetable broth: a low-sodium broth lets you control the salt.
- 1 small yellow onion, finely chopped: about 3/4 cup once diced.
- 2 garlic cloves, minced: fresh garlic gives the best flavor.
- 2 tablespoons all-purpose flour: thickens the sauce; a gluten-free blend works too.
- 1 tablespoon nutritional yeast: adds a cheesy, savory note that mimics “cream of mushroom” depth.
- 1 teaspoon soy sauce or tamari: for a deeper umami kick.
- 1/2 teaspoon salt: plus more to taste.
- 1/4 teaspoon black pepper: freshly ground if you have it.
- 1 1/2 cups crispy fried onions: check labels to make sure they’re vegan; French’s Original Crispy Fried Onions are accidentally vegan.
Variations / Substitutions
- Nut-free: Swap cashews for 1/2 cup raw sunflower seeds, soaked and blended the same way, for a creamy sauce without nuts.
- Gluten-free: Use a gluten-free flour blend and seek out gluten-free crispy fried onions, or make your own by coating thinly sliced onions in gluten-free flour and frying.
- No green beans: Broccoli florets or asparagus pieces work, though they need slightly different blanching times (4 minutes for broccoli, 2 minutes for asparagus).
- Extra umami: Stir in 1/2 cup sautéed cremini mushrooms with the onion if you want a mushroom-forward flavor.
- Make it oil-free: Omit the crispy fried onions and top with toasted breadcrumbs mixed with a little garlic powder; it won’t be the same but still adds crunch.
If you like this, try my Classic Vegan Mashed Potatoes for the full plant-based Thanksgiving spread.
How to Make Creamy Vegan Green Bean Casserole
Step 1: Blanch the Green Beans
Bring a large pot of salted water to a boil. Once it’s at a full rolling boil, add the 1 lb of trimmed green beans and cook for 5 minutes, until they turn bright green and are just tender but still have a little bite.
Immediately drain the beans and plunge them into a bowl of ice water. This stops the cooking and locks in that vivid color. After a few minutes, drain again and pat them completely dry with a clean towel, then set aside.
Step 2: Build the Creamy Sauce
While the beans cool, drain the soaked cashews and blend them with the 1 cup vegetable broth until completely smooth, about 1 minute. You’re aiming for a silky, opaque liquid with no grit; a high-speed blender works best, but a regular blender will get there if you give it a little extra time.
In a large skillet over medium heat, sauté the chopped onion in a splash of broth or a little oil for about 4 minutes, just until it softens and turns translucent. Add the minced garlic and cook 1 minute more, then sprinkle in the 2 tablespoons flour and stir constantly for another minute to cook out the raw flour taste. Slowly pour in the cashew cream mixture while whisking, then add the nutritional yeast, soy sauce, 1/2 teaspoon salt, and pepper. Raise the heat to medium-high and let the sauce simmer, whisking often, for 3 to 4 minutes. It will thicken to the consistency of a loose gravy. Turn off the heat and taste; the flavor should be savory and rich, with a gentle nuttiness from the cashews.
Step 3: Assemble the Casserole
Preheat your oven to 375°F (190°C). In a large bowl, toss the blanched green beans with the warm sauce until every bean is evenly coated. The sauce will be thick enough to cling without pooling.
Transfer everything to a 1.5-quart baking dish (an 8×8 square or a small oval casserole works). Spread the beans into an even layer, scraping every last bit of sauce over the top.
Step 4: Bake and Top with Crispy Onions
Slide the dish into the preheated oven and bake for 20 minutes. The sauce will bubble around the edges and thicken further, and the beans will finish cooking in the steam.
Carefully pull the casserole out, scatter the 1 1/2 cups crispy fried onions in an even layer over the top, and return it to the oven for 10 more minutes. The onions will turn deep golden and smell irresistible. Let the casserole rest for 5 minutes before serving, and scoop it hot, showing off that creamy sauce and crunchy crown.
A Few Notes Before You Bake
- Don’t skip the ice bath.: It’s the only way to guarantee the green beans stay vivid green and don’t overcook in the oven.
- If your sauce seems too thick, thin it with a splash more vegetable broth before combining with the beans. It should be pourable but not runny.
- For the crispest topping, add the fried onions only in the final 10 minutes of baking. They’ll frizzle and brown without getting soggy.
- To get ahead, assemble the casserole without the crispy onions up to 24 hours in advance. Cover and refrigerate, then add the onions and bake as directed, adding 5 extra minutes to the initial bake time to heat through.
- Leftover cashew cream?: Use it to thicken soups or drizzled over roasted vegetables.
Storing Leftover Casserole
- Refrigerate: Cool the casserole completely, then cover tightly and store in the fridge for up to 4 days.
- Reheating: The microwave is fastest, but the oven at 350°F for about 15 minutes brings back the crispy edges better. Note that the onion topping will soften; you can refresh it by adding a few fresh fried onions on top before reheating.
What Goes Well With Vegan Green Bean Casserole
It’s a natural beside a vegan lentil loaf or a stuffed seitan roast for a holiday centerpiece. The creamy sauce balances the spice of a Cajun-style tofu étouffée, and it’s right at home next to mashed potatoes and mushroom gravy for a comforting plate.
Frequently Asked Questions
Can I use frozen green beans instead of fresh?
Yes, and you can skip the blanching altogether. Thaw them completely, pat them very dry, and fold them directly into the sauce; they’ll cook through in the oven.
How do I make this casserole nut-free?
Swap the cashews for raw, unsalted sunflower seeds. Soak and blend them the same way, and the sauce will be just as creamy with a slightly earthier, nut-free base.
Can I prepare the whole dish ahead of time?
Absolutely. Assemble the casserole without the crispy onions, cover, and refrigerate for up to 2 days. When you’re ready, bake it for 25 minutes, add the onions, and bake 10 minutes more until hot and golden.
Why did my sauce turn out grainy?
This usually happens if the cashews aren’t soaked long enough or the blender isn’t powerful enough to break them down completely. Soak for at least 30 minutes and blend until silky, scraping down the sides as needed; straining through a fine-mesh sieve can rescue a gritty batch.
Creamy Vegan Green Bean Casserole Recipe
Ingredients
Method
- Blanch the green beans in boiling salted water for 5 minutes, then plunge into ice water to cool. Drain and pat dry.
- Blend the drained cashews with the vegetable broth until completely smooth. Set aside.
- Sauté the onion in a splash of broth or oil over medium heat for 4 minutes until soft, then add garlic and cook 1 minute. Stir in the flour and cook for 1 minute, then whisk in the cashew cream mixture, nutritional yeast, soy sauce, salt, and pepper. Simmer, whisking often, 3 to 4 minutes until thickened.
- Toss the green beans with the sauce, then transfer to a 1.5-quart baking dish. Bake at 375°F (190°C) for 20 minutes.
- Top with the crispy fried onions and bake 10 minutes more, until golden and bubbly. Let rest 5 minutes before serving.
