Vegan French Onion Soup

This Vegan French Onion Soup is pure deliciousness! It has the caramelized onions, cheesy bread topping, and the deep, rich flavor that everyone loves, except our version is totally dairy free. The perfect recipe for a cozy winter night.

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🍲 Why We Love This Recipe

• Packed with flavor: Traditional French onion soup gets its deep flavor from beef stock, wine and caramelized onions. In place of beef stock, we use vegetable stock and a few other ingredients to bump up that rich umami flavor. Otherwise, our vegan French onion soup is just like original, with just as much delicious flavor!
• Easy to make: Although this vegan French onion soup takes over an hour to cook, most of the time is hands off. Aside from slicing onions, there's not a whole lot of other prep time. All you have to do is stir every once in a while and be patient (your house will smell incredible!).
• Rustic, delicious comfort food: There's not a whole lot else to say: this vegan French onion soup is just pure deliciousness. Perfect for a chilly winter or fall evening, or any time you're craving something super comforting.

🧀 Ingredients

Here's what you'll need to make this vegan French onion soup:

📋 Ingredient Notes

• Onions: While you can use yellow, white, or red onions in your French onion soup, yellow onions are the traditional choice and that's what we prefer. Sweet onions are also an excellent choice and have a very similar flavor to yellow onions.
• Sherry: Sherry, a fortified wine made from white grapes, adds significant richness and depth of flavor to this vegan French onion soup. If you don't have any on hand, you can substitute with dry vermouth or more white wine.
• Soy sauce: While this isn't a traditional ingredient, since we aren't using beef broth, we rely on the soy sauce to add some needed richness and umami. Vegetable broth alone tends to be lacking a bit in that department, so don't suggest skipping the soy sauce. Note: if you're gluten free, feel free to substitute with tamari!
• Wine: Opt for a dry (non-sweet) white wine like Sauvignon or Pinot Grigio to prevent your soup from being too sweet.
• Flour: Regular all purpose flour or gluten free all purpose flour both work here.
• Thyme: Fresh really is best in this recipe. It adds just the right hint of earthiness to balance out all of that onion. We also love to sprinkle some on top of the finished soup.
• Vegan cheese: Classic French onion soup is topped with gruyere cheese. Since there isn't really a vegan equivalent, we opt for either vegan mozzarella or parmesan. For best result, we suggest a mix of the two, but one or the other will do.
• Sugar: A small pinch helps the caramelization process for the onions. Any sugar will work in this recipe.

🥣 Equipment

Our Staub Cast Iron Round Cocotte is absolutely perfect for cooking the base of this vegan French onion soup.

Its enameled interior is great for retaining and distributing heat, which makes it so easy to evenly cook this soup's more important ingredient - the onions! We've learned the hard way over time that in order to make perfect caramelized onions, the pan really does matter. Staub's cast iron enameled surface has never failed us and we use it almost daily for all sorts of soups, stews, skillet recipes, breads, desserts and so much more.

When it's time to add your broth, this cocotte has a 7 quart capacity, meaning you can safely double the recipe quantities if you're cooking for a crowd.

It also has a heavy, tight lid with a special design that helps to retain moisture for perfect simmering.

Unlike most other soup recipes, French onion soup requires an individual serving size in order to top with bread and cheese.

Staub Cast Iron Mini Cocottes are the right tool for the job! Since they're oven safe up to 900˚F (or 500˚F with the lid), there's no better option for browning up the cheese on individual bowls of soup in the oven. After all, half the fun of french onion soup is peeling the crisped up cheese off the sides of the bowl!

Not to mention, these mini cocottes are one of my absolute favorite kitchen items. They're adorable and make for a fun way to serve individual portions for dinner parties, holidays and so much more. You can use them for recipes like Shepherd's Pie, Mac and Cheese, Bread Pudding, custards and puddings, stews, fruit crisps and so much more.

🔪 Step-by-step Instructions

PREP: Preheat oven to 375˚F / 190˚C.

(1) Add olive oil to a large dutch oven over medium high heat. Add onions, sugar, soy sauce, and a pinch of salt and cook for 10 minutes, stirring often, until the onions soften and start to turn translucent.

(2) Reduce heat to medium low and continue cooking the onions, stirring every few minutes for 30-35 minutes.

(3) While the onions are cooking, brush both sides of baguette slices with olive oil. Transfer to baking sheet and bake for 12-15 minutes until golden brown and crispy, turning over halfway through. Set aside until ready to use.

(4) Once the onions have been cooking for 35 minutes, add in butter, garlic, salt, pepper, and thyme and cook for 10 additional minutes, until the onions are golden brown and caramelized.

(5) Stir in the flour until it coats the onions and increase heat to medium high. Add white wine and sherry and cook for 2-3 minutes.

(6) Add vegetable broth and bring to a boil. Once soup is boiling, reduce heat to medium low and simmer covered for 20-25 minutes.

(7) Ladle soup into mini cocottes arranged on a rimmed baking sheet. Top each cocotte with a slice or two of toasted baguette and sprinkle cheese on top. Bake for about 10 minutes, or until cheese is melted and lightly browned.

💭 Expert Tips

• At first, it will look like way too many onions, but we promise, they cook down a ton. By the time the onions are caramelized, they take up about ⅕ of the original space in the pot!
• Toast the bread ahead of time: In order to prevent the bread from getting completely soggy when you top the soup, toast it in the oven ahead of time. This makes for a crispy exterior that holds up well to the soup for the perfect textural contrast.
• Cook down until the soup is thick: To make sure the bread stays afloat on top of the soup, you'll want to make sure the broth cooks down a bit first. The addition of flour helps thicken it up more quickly, but you'll still need about 25 minutes of simmering after adding in the broth. (See photos 6 & 7 for visual guide on thickness of soup.)
• Vegan cheese doesn't always melt fully: Unfortunately, it can be hard to predict whether or not your vegan cheese will get nice and melty. Even if it doesn't look fully melted, we still suggest removing from oven after 10 minutes, otherwise it will start to harden up and burn after a certain point.
• Bake the cocottes on a baking sheet: It's total pain to transfer each mini cocotte to and from the oven, and it's very easy to spill. Place the cocottes on a baking sheet before filling with soup for easy transport. Pro tip: a smaller tray will keep the cocottes from slipping around to and from the oven.
• Storage: Store leftover soup in an airtight container in the refrigerator for up to 3-4 days (without the bread and cheese, of course). Top with bread and cheese and bake for 10 minutes to reheat before serving.
• Freezer storage: Let the soup cool completely, then transfer to an airtight container and freeze for up to 3 months. (Any longer and the flavor will diminish.) Let it thaw overnight in the refrigerator, then reheat.
• Make it gluten free: To make this vegan French onion soup gluten free, use gluten free all purpose flour and a gluten free baguette or similar bread option.

💭 Frequently Asked Questions

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