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Benihana Japanese Onion Soup Recipe (Copycat) 2026

The clear, savory-sweet soup served before every hibachi dinner — a faithful copycat recipe for home cooks.

Every Benihana hibachi dinner begins the same way: a steaming bowl of crystal-clear Japanese onion soup, light yet deeply savory, with thin mushroom slices and scallions floating on top. It’s simple, comforting, and surprisingly easy to replicate — this copycat Benihana onion soup recipe captures the delicate balance of sweet onion, rich stock and a whisper of ginger.

The secret is patience: slowly softened onions, a good-quality stock, and a light hand with seasoning. Ready in about 45 minutes, mostly hands-off.

Copycat Onion Soup Ingredients

  • 2 large sweet onions (Vidalia or Walla Walla), thinly sliced
  • 6 cups good chicken stock (or mushroom/vegetable stock for vegetarian)
  • 1 cup water
  • 2 tablespoons butter (or neutral oil)
  • 1 teaspoon fresh grated ginger
  • 2 cloves garlic, minced
  • 2 tablespoons soy sauce (low-sodium if preferred)
  • 1 teaspoon sugar
  • Salt and white pepper to taste
  • 4 oz mushrooms, very thinly sliced (for serving)
  • 2 scallions, thinly sliced (for serving)

How to Make It

  1. Melt the butter in a large pot over medium heat. Add the sliced onions with a pinch of salt and cook slowly, stirring occasionally, for 20–25 minutes until very soft, sweet and just golden — not browned.
  2. Stir in the ginger and garlic; cook 1 minute until fragrant.
  3. Add the stock, water, soy sauce and sugar. Bring to a gentle simmer.
  4. Simmer 15 minutes for the flavors to marry. Skim any foam.
  5. Taste and adjust: more soy for depth, a pinch of sugar if the onions weren’t sweet, white pepper for warmth.
  6. Strain (optional but recommended) for the signature crystal-clear broth, then return to the pot.
  7. Ladle into bowls and top each with a few raw mushroom slices and scallions — just like the restaurant.

Tips for Restaurant-Perfect Soup

  • Don’t rush the onions: the long, slow sweat is where the sweetness comes from.
  • Strain for clarity: Benihana’s soup is famously clear — a fine-mesh strainer gets you there.
  • Slice mushrooms paper-thin so they soften in the hot broth within seconds.
  • Keep it light: resist adding heavy seasoning — the charm is delicacy.
  • Make ahead: the broth keeps 4 days refrigerated and freezes well for 3 months. Add fresh mushrooms and scallions when serving.

Nutrition Note

This is one of the lightest restaurant soups anywhere — a bowl is roughly 30–60 calories, mostly from the stock and a little butter. Using low-sodium stock and going easy on the soy sauce keeps sodium in check. See our Benihana nutrition guide for the full picture.

Frequently Asked Questions

The restaurant version is a clear broth with onion, stock, subtle ginger and soy, garnished with thin mushroom slices and scallions. This copycat recreates it with sweet onions, chicken stock, ginger, garlic and soy sauce.

The restaurant soup is typically made with chicken-based stock. Use mushroom or vegetable stock in the copycat recipe for a vegetarian version.

The broth is simmered gently and often strained, giving it a crystal-clear appearance despite deep flavor from slowly cooked onions.

Yes — the strained broth freezes beautifully for up to 3 months. Add fresh mushrooms and scallions after reheating.

Thinly sliced white button mushrooms, added raw so they just barely soften in the hot broth.

Roughly 30–60 calories per bowl — it’s one of the lightest starters on the menu.

Conclusion

Benihana’s onion soup proves that simple can be spectacular. With sweet onions, good stock and a little patience, this copycat brings the restaurant’s beloved first course to your own table.

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