Vegetarian French Onion Soup

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💭 Why you’ll love this recipe

Great make-ahead dish. You can caramelize the onions and simmer the soup in advance, and add the cheese and French bread right before serving. Ultimate comfort food. Having a bowl of this hearty soup is enough to warm you up, especially during the colder months. The rich flavor combinations of caramelized onions, vegetable broth, and herbs make it so satisfying. Family favorite. This is a classic soup that never fails to impress. If you’ve never made it before, it’s guaranteed to be your family’s new favorite, and it’s always a hit with guests.

Variations & Substitutions

Onions. Yellow onions are traditional, but you can use a mix of yellow, white, and red onions for a more complex flavor. Garlic. Use fresh garlic for the best flavor, but in a pinch, you can use garlic powder. Brown sugar. To help caramelize the onions. Red wine. You can also use extra vegetable broth with a splash of balsamic vinegar for acidity. All-purpose flour. You can also use a 1:1 gluten-free flour blend or cornstarch for thickening the soup. Vegetable broth. Make you own vegetable stock or use store-bought vegetable broth. To make the flavor closer to beef broth, you can add a pinch of soy sauce of Worcestershire sauce. Seasonings. I used dried oregano, dried thyme, bay leaf, salt, and ground black pepper. You can also use fresh herbs. Gruyere cheese. Swiss cheese and emmental cheese work well, too. To make it vegan, you can use a vegan cheese that melts well or skip the cheese entirely. Baguette. You can toast the baguette slices for a delicious crunch. If you don’t have a baguette, you can use any crusty bread like ciabatta or sourdough. If you have gluten sensitivities, make sure to use gluten-free bread.

📖 How to make vegetarian French onion soup

Use a heavy-bottomed Dutch oven to maintain steady heat distribution. Let the red wine reduce completely to enhance the depth of flavor without overpowering the soup. Sprinkle the flour gradually while stirring to avoid lumps and ensure a smooth consistency. Simmer the soup uncovered to allow it to reduce slightly and intensify the flavors.

🍴 How to serve French onion soup

Serve this vegetarian soup as a starter for weeknight dinners, holiday gatherings, or date nights. I like to pair it with a simple salad like my caesar salad or garlic kale salad. It also goes well with pasta. Try serving it with my pasta fresca, pasta alla norma, or sun-dried tomato pasta.

🍴Storage and reheating suggestions

To store leftovers, transfer the soup to an airtight container and refrigerate for 3-4 days. You can also freeze the soup for up to 3 months. To reheat, transfer the soup to a saucepan and heat over medium heat. Add a splash of water or broth if needed. You’ll want to add the baguette slices and grated cheese just before serving to retain the texture and flavor.