This vegan green bean casserole will steal the show at your holiday table! It’s bursting with savory mushrooms and green beans in creamy white wine sauce, but it’s the homemade crispy fried onions that really take this savory side dish over the top.
Green bean casserole is nice. Yes, nice. Sorry, but that’s all I’m giving it. For me, it was always one of those holiday dishes that evokes an “Oh, that’s nice,” sort of reaction. No yelling, jumping, superhero stunts or anything like that…until I made this green bean casserole.
It’s vegan, but believe it or not, it’s the best green bean casserole I’ve ever had. With a creamy white wine mushroom gravy, and French fried onions, you better believe there was some excitement in my house a few weeks ago when I made this.
It’s meant to be a side, but we happily ate it as our dinner.
Vegan Green Bean Casserole Ingredients
Regular old green bean casserole is made with what I consider to be pretty boring ingredients. Green beans (okay, so these are good), canned cream of mushroom soup, and prepackaged French fried onions.
Maybe that’s why I never got excited about it in the past. Maybe that’s why my family always stuck with broccoli casserole.
My green bean casserole is made with homemade French fried onions. They take some extra work to make, but they also make your casserole taste incredible.
And instead of that cream of mushroom soup, we’ll be sautéing some fresh mushrooms in olive oil and making a creamy gravy out of white wine and non-dairy milk.
How to Make Vegan Green Bean Casserole
Your onions need to soak in a mixture of non-dairy milk and vinegar for a bit, so start by mixing that up, slicing your onions, and submerging them in the liquid.
While the onions soak, start on the casserole.
First, clean and slice your mushrooms. Heat up some olive oil in a skillet and cook the mushrooms for about 5 minutes on each side, until they’re browned and tender. Take them out of the skillet and transfer them to a plate.
Add some more oil to your skillet, heat it up, and add some onion. Cook the onion until it begins to soften up, for about 5 minutes. Now add some garlic and cook everything for about a minute more.
Next, add some wine to the skillet. Heat it up and let it simmer for a few minutes, until it reduces in volume by about half.
Now you’ll be adding some flour, just a bit a time, stirring between additions to form a smooth paste. You’ll probably get some cluming of the flour on your onion, but don’t worry too much about that.
Whisk in some non-dairy milk, a bit at a time, and stir in your cooked mushrooms some fresh thyme. Once the liquid is relatively smooth you can add your green beans. Let them simmer for about 10 minutes, until they begin to soften.
At this point you can either leave the mixture in your skillet (if you used an oven-safe one), or transfer it to a baking dish. Bake it until bubbly.
The French Fried Onion Topping
Fry your onions while the casserole bakes. Mix up some flour, paprika and salt in a bowl. Add your onions and stir until they’re well coated with the mixture.
Heat up some oil in a skillet — start with about 1/4 cup. When the oil begins to shimmer, add your onions. Fry the onions in batches if you can’t fit them all in the skillet without serious crowding. Cook them for a few minutes until the bottom layer begins to crisp, then flip them. Cook for a couple more minutes and flip again.
When all of the onions are golden and crispy, take them out of the skillet and transfer them to a paper towel lined plate to drain for a moment.
Top your casserole with the fried onions and dig in!
FAQ & Green Bean Casserole Tips
- If you have a medium-sized (10 to 12 inch) oven-safe skillet, use it to make the gravy and cook the green beans. This way you won’t need to transfer everything to a separate dish for baking.
- Be sure to prep and cook your mushrooms properly for the best texture and flavor:
- Don’t rinse them. They’ll soak up too much water, which will prevent browning. Instead, wipe them clean with a damp paper towel.
- Don’t crowd your skillet when cooking them. Cook them in batches if needed.
- Resist the temptation to stir them frequently while they sauté. Mushrooms brown best when they sit, undisturbed, for a few minutes on each side.
- I don’t cook with alcohol. Is there a substitute for the wine? Try subbing 1/4 cup of vegetable broth, and reduce the cook time in step 11 to about a minute — just long enough to bring it to a simmer
- If you do use the wine, check with Barnivore to ensure the brand you choose is vegan.
- I don’t feel like making French fried onions. Can I just use the packaged ones? Absolutely! I believe French’s brand is vegan.
- Make ahead options!
- The green bean casserole portion of the dish (sans onion topping) can be made up to a day in advance, refrigerated, and then baked the day of serving.
- You can begin soaking your onions early on the day of serving if you like.
- I recommend frying the onions just before serving, if possible. Otherwise, they’ll lose their crispness. If you absolutely have to make them ahead of time, try recrisping them under the broiler just before serving.
Vegan Green Bean Casserole
This vegan green bean casserole will steal the show at your holiday table! It's bursting with savory mushrooms and green beans in creamy white wine sauce, but it's the homemade crispy fried onions that really take this savory side dish over the top.
For the French Fried Onion Topping
- 10 ounces yellow onions (about 2 small or 1 large), thinly sliced into rings
- 1 1/2 cups unflavored and unsweetened non-dairy milk
- 1 1/2 tablespoons white vinegar
- 1 cup all-purpose flour
- 3/4 teaspoon salt
- 1/2 teaspoon black pepper
- 1/2 teaspoon paprika
- 1/2 cup canola oil (or as needed), or high heat oil of choice
For the Green Bean Casserole
- 3 tablespoon olive oil, divided
- 6 ounces white button mushrooms (about 2 cups), cleaned and sliced
- 1 medium onion, diced
- 2 garlic cloves, minced
- 1/2 cup dry white wine
- 1/4 cup all-purpose flour
- 2 cups unflavored and unsweetened non-dairy milk
- 2 tablespoons soy sauce
- 1 teaspoon dried thyme
- 5 cups fresh green beans, cut into 2-inch pieces
- Salt and pepper to taste
Begin by soaking the onions in preparation for frying them. Stir the milk and vinegar together in a large bowl.
Add the onions to the milk mixture. Allow them to soak for at least 30 minutes, stirring occasionally.
White the onions soak, make the casserole. Coat the bottom of a medium skillet (preferably an oven-safe one) with 2 tablespoons of olive oil and place it over medium heat.
When the oil is hot, add the mushrooms in an even layer, cooking them in batches if needed to avoid crowding.
Cook the mushrooms for about 5 minutes on each side, until tender and browned, and then transfer them to a plate.
Add the remaining tablespoon of olive oil to the skillet.
Give the oil a minute to heat up, and then add the onion.
Sweat the onion for about 5 minutes, until soft and translucent.
Add the garlic and cook it for about 1 minute more, until very fragrant.
Stir in the wine, raise the heat slightly and bring it to a simmer.
Allow the wine to simmer for about 5 minutes, until reduced by about half.
Sprinkle in the flour, a bit at a time, stirring between each addition to form a paste that coats the onions.
Begin pouring in the milk, a bit at a time, whisking the milk and flour mixture together between each addition.
Return the mushrooms to the skillet, and stir in the soy sauce, thyme, and green beans.
Raise the heat and bring the liquid to a simmer. Allow it to cook, stirring occasionally, until the green beans are tender but still a tad on the firm side, 10 to 15 minutes.
While the mixture simmers, preheat the oven to 350°F.
When the green bean mixture is done simmering, remove the skillet from the heat and season it with salt and pepper to taste.
If your skillet is oven-safe, place it directly into the oven. Otherwise, transfer the mixture to a 9 x 9 inch baking dish and then to the oven. Bake for about 20 minutes, until bubbly.
While the casserole bakes, fry the onions. Stir the flour, salt, pepper, and paprika together in a large bowl.
Working in batches, remove the onions from the milk mixture, shaking off any excess liquid, and transfer them to the flour mixture, stirring to coat the onions evenly.
Very generously coat the bottom of a large skillet with the oil (you want at least 1/8 inch) and place it over medium-high heat.
When the oil begins to shimmer, add a layer of onions — enough to cover most of the bottom of the skillet without crowding.
Fry the onions for about 2 minutes, until the bottom of the onion layer begins to brown and crisp, then flip the onions.
Fry the onions for about 2 minutes more, then flip them again.
Fry for about 2 minutes more. By now all of the onions should be pretty crispy. Transfer them to a paper towel-lined plate.
Repeat until all of the onions are cooked, adding oil to the skillet as needed between batches.
When the casserole has finished baking, remove it from the oven and top it with the onions.