This fantastic, light Benihana Onion Soup is a fan-favorite at the popular Japanese Steakhouse and it's surprisingly easy to make! The soup goes by many names, but is always loaded with onion flavor then topped with mushrooms, scallions, and fried onions!
In a saucepan, combine the vegetable base for the broth: carrots, celery, onion, and garlic with a tablespoon or two of water or chicken broth. Saute the vegetables over medium-high heat until fragrant.
Add the chicken broth and water to the sauteed vegetables. Bring to a boil then reduce heat and simmer for 30 minutes.
Using a fine-mesh sieve, drain the broth into a clean bowl and throw away the strained vegetables. Return the clear broth to your saucepan and keep on low heat while serving.
Serve with 6-8 thinly sliced mushrooms, garnished with sliced green onions and fried onions.
Adding ½ tablespoon of beef bouillon granules and ⅛ teaspoon of ginger powder greatly enhances this soup flavor. Season to taste with salt and pepper. Or you can puree your strained cooked vegetables and add them back to your soup.