The Best Homemade Vegetarian French Onion Soup
This homemade French onion soup is rich, savory and packed with deep caramelized flavor. Topped with melty cheese toasts, it’s the ultimate comfort food and tastes just like the classic French onion soup you’d find at your favorite bistro.
Few soups feel as cozy and indulgent as a steaming bowl of traditional French onion soup. This vegetarian French onion soup recipe captures all the deep flavors and gooey cheese you love, without the beef stock.
Whether you’re enjoying this for the first time or it’s already one of your favorite soups, this easy French onion soup recipe proves that plant-based swaps like vegetable broth, vegan butter, and even vegan cheese can still create an unforgettable bowl of soup.
This soup is part of our easy homemade soup series, and while it’s a bit more hands-on than a dump-and-go slow cooker recipe, the reward is well worth the effort. It’s a perfect dinner party starter, cold-weather dinner or stay-home date night dish.
Why You’ll Love This French Onion Soup
- Slow-caramelized onions add a deep, savory broth and incredible depth of flavor
- Brothy base made with mushroom broth, low sodium vegetable broth, or homemade vegetable stock
- Topped with melty cheese (vegan or traditional), broiled until bubbling and golden
- Served with crusty French bread or cheesy croutons in oven-safe bowls
- Cozy, affordable and truly the ultimate comfort food
- Perfect freezer meal base — just add fresh cheese toast when serving
- Elegant but unfussy — no fancy equipment required
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Ingredients You’ll Need for Homemade French Onion Soup
To make this savory, comforting Homemade French Onion Soup recipe, you’ll need a few simple ingredients:
- Yellow onions (or white onions for a slightly milder flavor)
- Unsalted butter
- Olive oil
- Garlic
- Dry white wine
- Vegetable broth, mushroom broth or low sodium veggie broth (you can also use beef broth or stock if you aren’t a vegetarian)
- Bay leaves
- Dried thyme
- Salt and black pepper, to taste
- Baguette
- Grated Gruyere cheese
How to Make French Onion Soup at Home
Peel and slice the onions. The best way to cut onions for caramelizing is to slice them lengthwise (pole-to-pole) into thin, even slices, about 1/4-inch thick. Make sure they’re cut evenly. This method helps the onions maintain their shape during cooking, while also ensuring even caramelization and helping to prevent burning.
Caramelize the Onions (The Heart of the Soup): In a large pot or Dutch oven, melt butter and olive oil over medium heat. Add sliced onions and stir to coat.
Cook for 15 minutes, stirring frequently, until soft and translucent.
Then, reduce heat to medium-low and cook for 30–40 more minutes, stirring occasionally, until onions are deep golden brown. Add garlic during the final few minutes, just long enough to soften without burning.
💡 Pro Tip: The caramelization step can’t be rushed. Low and slow is what creates that rich, sweet onion flavor French onion soup is famous for.
Deglaze & Simmer the Broth: Turn the heat up to medium-high and add the dry white wine, scraping the bottom of the pot to release all the flavorful brown bits. Let it simmer and reduce by half, about 5 minutes.
Add broth, bay leaves, thyme, salt, and pepper. Bring to a gentle simmer, then reduce heat to low and cook for 30 minutes. Discard bay leaves before serving.
Toast the Bread with Cheese: Preheat your broiler. Arrange your bread slices on a baking tray, sprinkle with Gruyère cheese, and broil for 2–3 minutes until the cheese is golden and bubbly.
Keep an eye on them — they can burn quickly!
Serve & Enjoy: Ladle hot soup into bowls and top each with a cheesy toast. Serve immediately, and get ready to swoon.
Expert Tips for the Best French Onion Soup
For the best homemade French Onion Soup possible, be sure to follow these expert cooking tips:
- Slice onions thin and evenly for consistent caramelization.
- Don’t rush the onions. The caramelizing step is what builds the soup’s depth.
- No white wine? Try dry sherry or omit and add a splash of balsamic vinegar instead.
- Vegetarian version? Use mushroom or vegetable broth instead of beef stock and a plant-based butter.
- Make-ahead tip: The soup base freezes beautifully. Just add fresh toast and cheese when ready to serve.
- No Gruyere cheese? Try mozzarella, sharp cheddar or even grated Swiss.
What to Serve with French Onion Soup
French onion soup is a delicious meal on its own, but if you’re looking for a more filling option, try serving it with:
- Mixed greens salad with a bright vinaigrette
- Roasted vegetables or a savory tart
- Crisp white wine or sparkling water with lemon
- A cozy blanket and your favorite playlist
More Soups You’ll Love
- San Marino Chicken Fideo Soup – light and lemony
- Slow Cooker Vegan Butternut Squash Soup – creamy and cozy
- Mexican Meatball and Chicken Taco Soup – hearty with a kick
FAQs About Homemade French Onion Soup
What onions are best for French onion soup?
Yellow onions are ideal for their balance of sweetness and flavor. Sweet onions can work, but the end result may be a bit milder.
Can I use red wine instead of white?
Yes! Red wine makes for a deeper, richer soup. Choose a dry wine, like cabernet or merlot.
What cheese is best for French onion soup?
Gruyère is the traditional choice for its nutty, melty quality. Swiss or provolone are great backups.
Can I make this ahead of time?
Yes. The soup base can be made days ahead or frozen for up to 3 months. Add the cheesy bread fresh when serving.
Homemade French Onion Soup
This homemade French onion soup is rich, cozy, and packed with deep caramelized flavor. Topped with golden Gruyère toasts, it's comfort food at its finest and tastes just like the pricey restaurant version.
Ingredients
- 2.5 lbs of yellow onions, thinly sliced
- 2 tablespoons of unsalted butter
- 1 tablespoon of olive oil
- 2 cloves of garlic, minced
- 1/2 cup of dry white wine
- 6 cups of vegetable stock
- 2 bay leaves
- 1/2 teaspoon of dried thyme
- Salt, to taste
- Ground black pepper, to taste
- 8 slices of baguette
- 1 cup of grated Gruyère cheese
Instructions
- Peel and slice the onions. The best way to cut onions for caramelizing is to slice them lengthwise (pole-to-pole) into thin, even slices, about 1/4-inch thick. Make sure they're cut evenly. This method helps the onions maintain their shape during cooking, while also ensuring even caramelization and helping to prevent burning.
- Caramelize the Onions: In a large pot or Dutch oven, melt the butter with the olive oil over medium heat. Add the sliced onions and stir to coat them with the butter mixture. Cook for about 15 minutes, stirring frequently, until the onions start to soften and turn translucent.
- Reduce the heat to medium-low and continue cooking, stirring occasionally, for about 30-40 minutes, or until the onions are deeply caramelized to a rich golden brown color. Add the garlic in the last few minutes of cooking, being careful not to let it burn.
- Deglaze and Simmer: Increase the heat to medium-high and pour in the white wine to deglaze the pot, scraping up any browned bits from the bottom with a wooden spoon. Let the wine reduce by half, which will take around 5 minutes.
- Add the stock, bay leaves, and thyme. Season with salt and pepper. Bring the mixture to a simmer, then reduce the heat to low and let it gently simmer for about 30 minutes. This will allow the flavors to meld together. Remove the bay leaves before serving.
- Broil the Cheese: Preheat your broiler. Place the baguette slices on a baking sheet, top with grated cheese and broil them in the preheated oven until the cheese is bubbly and golden brown, about 2-3 minutes. Watch carefully to prevent burning.
- Serve: Carefully remove the baguette from the oven and place them in the bowl of soup. Serve immediately. Enjoy your delicious homemade vegetarian French Onion Soup!
Nutrition Information:
Yield: 4 Serving Size: 1Amount Per Serving: Calories: 894Total Fat: 26gSaturated Fat: 12gTrans Fat: 0gUnsaturated Fat: 11gCholesterol: 53mgSodium: 2499mgCarbohydrates: 129gFiber: 9gSugar: 24gProtein: 34g
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Homemade French Onion Soup (Rich, Buttery & Absolutely Worth It)
This Homemade French Onion Soup recipe is proof that with a few humble ingredients and a bit of patience, you can create something truly special. It’s warm, rich, slightly sweet, and perfectly cheesy — everything you want on a chilly night.
Pin it now and save it for your next comfort food craving.
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