The Best Vegan Green Bean Casserole

A homemade chunky mushroom gravy brings fresh flavor to this green bean casserole, which is a whole-food, plant-based take on the classic holiday dish.

By Darshana Thacker Wendel,



  • 1 medium yellow onion, thinly sliced
  • 1 tablespoon ground flaxseed
  • 2 pinches sea salt
  • 2 pinches black pepper
  • 24 ounces fresh green beans, trimmed and cut into bite-size pieces (8 cups)
  • 1 tablespoon sliced almonds


  • 1 yellow onion, cut into ½-inch dice (2 cups)
  • 16 ounces mushrooms, sliced (8 cups)
  • 6 cloves garlic, minced
  • ⅓ cup oat flour
  • 2 cups low-sodium vegetable broth
  • 2 tablespoons white wine vinegar
  • 1 tablespoon Italian seasoning
  • Sea salt and freshly ground black pepper, to taste


  • Preheat oven to 350°F. Line a baking sheet with parchment paper.
  • In a mixing bowl, combine thinly sliced onion, flaxseed, salt, and pepper. Mix well to coat onions; let sit for 5 minutes.
  • Spread onions on prepared sheet and bake 15 minutes until lightly brown around the edges. Set aside.
  • Meanwhile, place green beans in a steamer basket in a large saucepan. Add water to just below basket. Bring to boiling. Steam, covered, about 10 minutes or until tender. Remove from heat and transfer beans to a 2½-qt. baking dish.
  • To make gravy, combine diced onion, mushrooms, and garlic in a saucepan over medium heat. Cover pan and cook, stirring occasionally, for 7 to 10 minutes or until onions start to turn translucent. The mushrooms will release enough liquid to keep the vegetables from sticking to the pan.
  • In a medium bowl, whisk together oat flour, broth, vinegar, and Italian seasoning; season with salt and pepper. Add broth mixture to mushroom mixture; cook for 3 to 5 minutes more, or until gravy thickens.
  • Transfer half of gravy to a blender. Purée until smooth. Return puréed mixture to saucepan and stir well.
  • Pour the gravy over the green beans in the casserole dish. Scatter browned onions and almonds over the top. Bake about 20 minutes or until heated through.

Comments (10)

(5 from 3 votes)

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Does 16 ounces of mushrooms actually equal 8 cups or is that a typo?


I don’t usually like green beans, but this was delicious!!


With 8 ounces being a cup the 24 ounces of green beans should be 4 cups and the 16 ounces of mushrooms should be 2 cups.


Can this be made ahead and just warmed up?


I will add a half cup of nutritional yeast to help give it the creaminess it's lacking compared to the traditional recipe.

Cruelty-Free Caty

This was absolutely a hit amongst all!! HOWEVER, despite the fact i spend my Thanksgivings with an Italian chosen-family, i still wasn't keen on the Italian seasoning... esp not for Thanksgiving! Instead, i combined generous shakes of Poultry seasoning (yes, its vegan), garlic salt, and sage, with a timid splash of dried thyme and rosemary. HIGHLY RECOMMEND this combo. I also added a tiny bit of almond flour flour to the baked onions, as the flax meal alone made me suspicious, and hardly coated them. I used this flour instead of oat, cuz i didnt have time to grind up oats and thusbwas in the cupboard. The process itself was perfect tho, nit too extensive, not soaking in oil, salt, sugar or the like. Thanks PCRM! Its a keeper.

(me again)

(guess i shouldnt have disabled auto-correct whoops! )


I followed your suggestions—they were right on! Thanks! I also added 1 T of tapioca flour to the broth to thicken it up a bit. I wasn’t sure if the oat flour would sink to the bottom when leftovers were served. Maybe it would be fine (was it?) but I didn’t want to take the risk. I also doubled the almonds—sooo good! A brilliant topper. I’ll be making this every year! Tasty and low fat!

Carlysa Jackson

Could celery replace mushrooms? I’m allergic.

Leslie Rayle

I am trying celery because my sister doesn’t like mushrooms at all! Fingers crossed!

About the Author

Headshot of Darshana Thacker

About the Author

Darshana Thacker Wendel

Darshana Thacker Wendel is a whole-food, plant-based chef and former culinary projects manager for Forks Over Knives. A graduate of the Natural Gourmet Institute, she is the author of Forks Over Knives: Flavor! She created the recipes for Forks Over Knives Family and was a lead recipe contributor to the New York Times bestseller The Forks Over Knives Plan. Her recipes have been published in The Prevent and Reverse Heart Disease Cookbook, Forks Over Knives—The Cookbook, Forks Over Knives: The Plant-Based Way to Health, and LA Yoga magazine online. Visit and follow her on Instagram for more.
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