Go Back
vegan green bean casserole

Best Vegan Green Bean Casserole

A creamy, crowd-pleasing vegan twist on the classic holiday green bean casserole. Made with fresh or frozen green beans, a homemade mushroom sauce, and crispy baked onions, this dish is perfect for gatherings, packed with plant-based nutrition, and full of comforting flavors.
Print Recipe Pin Recipe
Prep Time 20 minutes
Cook Time 30 minutes
Total Time 50 minutes

Ingredients
  

For the Casserole:

  • 1 lb fresh green beans or frozen, trimmed and cut
  • Ice water for blanching
  • 1 tbsp olive oil
  • 1 cup cremini mushrooms thinly sliced
  • 2 cloves garlic minced
  • 2 tbsp all-purpose flour or gluten-free
  • 1 ½ cups plant-based milk unsweetened almond or soy
  • 1 tbsp nutritional yeast
  • 1 tsp thyme or rosemary
  • Salt and pepper to taste
  • 1 tbsp vegan butter

For the Crispy Onion Topping:

  • 1-2 yellow onions thinly sliced
  • ½ cup all-purpose flour or gluten-free alternative
  • 1 tsp salt
  • ½ tsp black pepper

Instructions
 

Prep the Green Beans:

  • Blanch trimmed green beans in boiling water for 2–3 minutes. Transfer immediately to an ice bath. Drain and pat dry.

Make the Mushroom Sauce:

  • In a skillet, heat olive oil. Sauté mushrooms until moisture is released. Add garlic and cook 2–3 minutes. Stir in flour to form a roux. Gradually whisk in plant-based milk until smooth. Add nutritional yeast, herbs, salt, and pepper. Simmer until thickened.

Make Crispy Onions:

  • Toss sliced onions with flour, salt, and pepper. Spread on a parchment-lined baking sheet and bake at 425°F (218°C) for 15–20 minutes, flipping halfway.

Assemble the Casserole:

  • In a 9x13 inch dish, layer blanched green beans. Pour over the mushroom sauce. Top with half of the crispy onions.

Bake:

  • Bake at 375°F (190°C) for 25–30 minutes, until bubbly. Add remaining crispy onions during the last 10 minutes for extra crunch.

Serve:

  • Let cool slightly and serve warm.

Notes

  • Make the crispy onions up to 2 days in advance and store in an airtight container.
  • You can substitute almond milk with oat, soy, or cashew milk.
  • Frozen green beans are a good alternative when fresh are unavailable. Just thaw and pat dry.
  • For a gluten-free version, use gluten-free flour and topping.
  • Try mushroom variations like shiitake or oyster for different flavors.
  • To reheat, cover with foil and bake at 350°F for 20–25 minutes.
Keyword dairy-free casserole, gluten-free optional, plant-based holiday recipe, vegan comfort food, vegan green bean casserole, vegan thanksgiving side