This Vegan French Onion Soup Recipe is a delicious plant-based and gluten-free recipe that’s both cozy and luscious. It’s flavorful, savory, cheezy, and carby and not that difficult to make, either. The onions have a long cook time but that’s mostly unattended gentle simmering.

What Type of Onions Should I Use for Vegan French Onion Soup?
Yellow onions are perfect for this recipe. Nothing fancy, just use the common ones you find either singly or in bags in your produce department. Six Onion Soup is a version of the soup that uses six different types of onion. I made a Six Onion Gravy that’s awesome. This is kind of fun and can add a bit of complexity but for this soup, we’re just going to use yellow onions. French Onion soup uses yellow onions so we’re sticking with tradition here.

Vegan French Onion Soup is Delicious and Easy to Make
Vegan French Onion Soup is totally delicious and surprisingly easy to make. Just simmer a giant pile of yellow onions in oil and vegan butter. The goal is not to brown the onions but to let them gently simmer for a long time to allow them to caramelize. I kept my burner on low and every stove is different, but you’ll want just the gentlest of simmers.

Stir often to make sure nothing is sticking to the pan. If the temperature is as gentle as it should be, nothing should stick very much.
Once the onions are done cooking, you can deglaze the pan with half of a cup of your favorite red or white wine. Grape juice or non-alcoholic wine would also work. Any of these will add a bit of depth of flavor. But don’t worry if you don’t have any. Just use all vegetable broth.

Overnight Onions with the Slow Cooker Option
Caramelizing the onions in a slow cooker overnight is even easier than letting them simmer gently on the stove. Start the onions the evening before. Add butter, olive oil, and the sliced onions to the slow cooker or crockpot. Cook on high for several hours or overnight. Caramelized onions are so easy this way.
Ingredients in Vegan French Onion Soup
Caramelized Onions are the obvious star of this dish. Use yellow onions. They’re easy to find and usually relatively inexpensive.
Vegetable Stock or Vegetable Broth deliciously takes the place of beef broth in classic French onion soup. The soup is just as or more delicious with an equal depth of flavor.
Garlic adds even more pungent allium flavor. Just add a clove or two of finely minced garlic.
Bay Leaves have a distinct flavor and are great in soups and stews. Traditional French Onion Soup uses bay leaves to add more flavor and we do here as well.
Fresh Thyme or Dried Thyme is a lovely and traditional flavor to add to this plant-based delight. Use fresh minced but, if you don’t have that, just use the dried version.
White Grape Juice can be a substitute for red wine or white wine, which are in the traditional version of this soup. Or, for this alcohol-free and vegan version, you can also omit either and use all vegetable broth, which is what I did.
French Baguette Slice or Good Bread for Toasting is invaluable here. A crusty baguette sliced would be perfect! Any good bread will work in this delicious soup, though.
Plant-Based Cheese Shreds are used in this recipe instead of the traditional gruyere cheese. A light-colored cheese, such as vegan mozzarella, looks and tastes beautiful. There are so many brands of vegan cheese available now. I’m still a fan of Daiya and it’s readily available but Vevan, Miyoko’s, and even the Simple Truth (Kroger brand) are really delicious and melt well.

Adding the Toast

Just like classic French Onion Soup, this soup has a piece of toast made from good bread on top of the soup and under the cheese. I suspect the bread is to keep the cheese afloat! Just cut it to fit your particular bowl. I used my favorite gluten-free bread.

Use Oven-Proof Bowls
This is important. Ladle the soup into bowls and pile it high with vegan cheese. It’s crucial to use oven-proof or oven-safe bowls here. The plant-based cheese will melt and brown and become gooey and delicious under a hot broiler.
Remember the bowl handles are going to be super hot when they come out of the oven. Use heatproof oven mitts, pot holders, or a thick towel to handle the hot bowls.
Six Onion Soup (Vegan Gluten Free)

Six Onion Soup is a delicious vegan and gluten-free recipe that's both cozy and luscious. It's not that difficult to make, either. The onions have a long cook time but that's mostly unattended gentle simmering.
Ingredients
- 5 cups thinly sliced yellow onions
- 2 tablespoons olive oil
- 2 tablespoons vegan butter
- 4 cups vegetable broth
- 1 teaspoon salt
- 1 teaspoon garlic powder or use that amount of garlic paste or mashed garlic (I used black garlic paste)
- 2 teaspoons dried parsley flakes
- 2 teaspoons dried chives
- 1/2 teaspoon dried thyme
- 1 bay leaf
- 3 cups water
- salt and pepper to taste
- bread slices
- 16 oz vegan cheese shreds
Instructions
1. Peel the outer papery skin off the onions and then slice thinly into strips about 2 inches long.
2. Heat the olive oil and butter in a large heavy-bottomed skillet over medium heat, Add the sliced onion and let heat through. Then reduce the heat to low-medium and let the onions very gently simmer for about 2 hours. The onions will be caramelized and so cooked they're mushy.
3. Pour in the vegetable broth, and water, add the spices and add salt and pepper to taste.
4. Let the soup come to a gentle simmer. Simmer for about an hour.
5. Once the soup is simmered and reduced. Ladle some into oven-proof bowls and add a piece of good toast on top of the soup. On the toast, add about a quarter to a half-cup of vegan cheese shreds. I used a new to me mozzarella by Vevan but just use your favorite. Light-colored cheeses are going to look really nice.
6. Place the soup and toast and cheese bowls under a broiler for a few minutes to melt and slightly brown the cheese.
7. Serve hot and bubbly.
Enjoy!
Nutrition Information:
Yield:
8Serving Size:
1Amount Per Serving: Calories: 281Total Fat: 14gSaturated Fat: 3gTrans Fat: 1gUnsaturated Fat: 10gCholesterol: 0mgSodium: 1072mgCarbohydrates: 31gFiber: 2gSugar: 21gProtein: 9g
La Joie Appétit! XOXO

Hello! I’m Lisa, a vegan artist, photographer, author, Vegan Life Coach Educator, and RYT 200 yoga teacher. I love showing others how simple and delicious a plant-based diet can be. I draw and paint, cook, write, take lots of pics, eat lots of chocolate, and practice gratitude daily.