Charred Onion Soup

French onion soup is a classic dish that originated in France and has become beloved around the world for its rich flavor and comforting qualities. With the amount of time and patience it takes, along with the animal products, we sought a plant-based crash course version. 

Traditionally, the soup is made with caramelized onions slowly cooked to bring out their natural sweetness, the soup is simmered in a savory beef broth, often enhanced with herbs like thyme and bay leaf. It’s typically served in a crock, topped with a slice of crusty bread and a generous layer of melted Gruyère cheese, and broiled until bubbly and golden.

This dish reflects the beauty of simple ingredients transformed through time and technique. While it began as a humble peasant dish, French onion soup has found its way into fine dining menus, celebrated for its balance of sweet, salty, and savory notes. Whether enjoyed on a chilly evening or served as a starter for a hearty meal, it continues to be a timeless comfort food that warms both body and spirit.

We wanted to capture that essence in a way modern peasants can pull off on a weeknight! Using the broiler for the onions is the key, as we can char them to unlock sweet and smoky notes, which add a lot of complexity to the finished soup. Then, there are a variety of umami enhancers that bring even more to the party. 

A vital ingredient in the flavor development of this soup is miso. Miso is a traditional Japanese seasoning made by fermenting soybeans with salt and kōji, a type of mold typically grown on rice, barley, or soybeans. The result is a thick paste rich in umami, the savory fifth taste. Miso varies in color and flavor depending on the ingredients and length of fermentation—white miso is lighter and sweeter, while red miso is darker and more intense. Beyond its deep, earthy taste, miso is also prized for its nutritional value, offering protein, probiotics, and essential minerals.

One of the most common uses of miso is in miso soup, a staple in Japanese cuisine often served alongside meals. The soup starts with a base of dashi, a clear broth typically made from dried kelp and bonito flakes, into which miso paste is dissolved. The result is a comforting, savory soup that highlights miso's umami depth while remaining light and nourishing. 

The miso plays exceptionally with the sweetness of the charred onions and brings that savory note that is so common when using beef broth. Other important additions include sweet paprika and Dijon mustard, which bring spice and sharpness to balance out the strong, sweet, and savory notes. Parmesan cheese rind is a welcomed addition, and while not vegan, is a sustainable way to use every part of the cheese that you bought!

Finally, the addition of white wine in the roasting pan adds a lot of character to the soup, as you always want to capture those roasty brown bits of flavor. As the soup finishes bubbling, you want to serve it with sliced chives and an extra sprinkle of parmesan cheese. Enjoy while hot, or save some for the next day for an even deeper flavor!

Charred Onion Soup

This vegan spin on the classic French onion soup uses a variety of umami bombs to achieve that incredible savory depth of flavor in a fraction of the time. Still perfect for dipping a crunchy toasted baguette!

Recipe and Photography by Sam Burgess

Forge To Table Knives

Prep Time: 15 minutes

Cook Time: 55 minutes

Servings: 4-6

Ingredients:

• 4 large sweet onions, sliced into ½”-thick rounds

• 2 tablespoons soy sauce

• 2 tablespoons miso

• 2 tablespoons brown sugar

• 3 tablespoons Dijon mustard

• 2 each bay leaves

• 1 teaspoon paprika

• ¾ teaspoon ground ginger

• 8 cups roasted garlic or vegetable broth (homemade or storebought) 

• 1 parmesan cheese rind (optional- not vegan)

• 1 cup white wine

• 1 baguette, sliced into rounds and lightly toasted

• Chives, sliced, for garnish

• Nutritional yeast or grated parmesan cheese, for garnish (optional)

Directions:

1. SLICE. Preheat the broiler in the oven. Using your Forge To Table Nakiri knife, slice the onions into ½”. thick rounds. Be careful so the onion does not slip away while slicing. 

2. BROIL. Place the onions on a rimmed baking sheet and drizzle with soy sauce, tossing to coat. Broil, stirring once, until the onions are softened and charred in some places, 15-20 minutes total (this may depend on the power of your broiler, be sure to check them every 5 minutes). 

3. SIMMER. Meanwhile, in a large soup pot, add miso, brown sugar, Dijon mustard, bay leaves, paprika, ground ginger, and roasted garlic or vegetable broth. Bring to a boil, add parmesan rind (if using), and reduce heat to a low simmer. Stir occasionally so the cheese doesn’t stick to the bottom of the pot.

4. COMBINE. Once the onions are done broiling, add them to the simmering pot. Add the white wine to the pan the onions were cooked in, scraping up any browned bits, and add the wine to the pot. Continue to cook until the stock darkens and the onions become silky and soften, about 30-45 minutes. It can simmer for longer if desired. 

5. SERVE. Discard bay leaves. Check seasoning of the soup and add some salt and pepper, if desired. Ladle the soup into bowls and serve with a sprinkle of sliced chives, nutritional yeast, or parmesan (optional), and some toasted baguette. Enjoy!

Chef’s Notes:

• Roasted garlic broth is an incredible plant-based flavor enhancer. We used it from a base, but you can make your own, too. 

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