I cracked the secret to a light, restaurant-style Japanese clear onion soup that uses just nine ingredients, is ready in 30 minutes, and stays perfectly gluten-free, low-carb, keto, paleo and Whole30 friendly.
I’m borderline obsessed with this Japanese clear onion soup. It tastes like the hibachi menu version, but cleaner, sharper, and somehow more honest.
I love the way thinly sliced yellow onions become silky and bright, barely sweet, cutting through a simple bowl of low sodium chicken broth. It’s light but not insubstantial.
I eat it when I want something thoughtful without effort. And yes I sip it straight from the bowl, spoon optional.
Pure flavor, zero fuss. Short ingredient list.
Big payoff. Keeps me coming back on repeat, no questions asked.
Clarity is the point, and I want it constantly.
Ingredients
- Basically, sweet, soft base that makes the broth feel cozy.
- Plus, savory liquid backbone; you’ll get more character with dashi.
- Adds salty umami depth; use tamari to keep it gluten free.
- Basically, a hint of sweet brightness; skip it for strict keto.
- Adds silky richness and mouthfeel; it’s what makes the broth feel rounder.
- Gives subtle, savory lift without overpowering the gentle onion flavor.
- Just a little goes far; toasty finish and aromatic kiss.
- Start small; salt tightens flavors and brings everything into balance.
- Plus, crisp freshness and color; sprinkle on right before serving.
Ingredient Quantities
- 2 large yellow onions, thinly sliced (about 4 cups sliced)
- 6 cups low sodium chicken broth (or dashi for a more authentic flavor)
- 2 tablespoons gluten free tamari or soy sauce (use tamari to keep it gluten free)
- 1 tablespoon mirin (optional if you want a touch of sweet, omit for strict keto)
- 1 tablespoon unsalted butter
- 1 teaspoon garlic powder
- 1 teaspoon toasted sesame oil
- salt to taste (start with 1/2 teaspoon)
- 2 green onions (scallions), thinly sliced for garnish
How to Make this
1. Slice 2 large yellow onions thinly so you get about 4 cups sliced, dont rush this part it makes the soup.
2. Melt 1 tablespoon unsalted butter in a medium pot over medium low heat.
3. Add the sliced onions and cook gently, stirring every few minutes, until they’re soft and translucent about 12 to 15 minutes. dont let them brown too much or the broth wont be clear.
4. Stir in 1 teaspoon garlic powder and 1 teaspoon toasted sesame oil, cook 30 seconds to wake up the flavors.
5. Pour in 6 cups low sodium chicken broth or use dashi for a more authentic flavor, then add 2 tablespoons gluten free tamari or soy sauce and 1 tablespoon mirin if using.
6. Bring to a gentle simmer, reduce heat and let it simmer uncovered for 10 minutes, skim any foam or bits that rise so the soup stays clear.
7. Taste and add salt starting with 1/2 teaspoon, then adjust to your liking. remember tamari can be salty so taste first.
8. Remove from heat and let sit a minute, the flavors will settle.
9. Ladle into bowls, garnish with thinly sliced green onions and an extra drop of sesame oil if you like.
10. Serve hot with rice or enjoy on its own, this makes about 4 servings and takes around 30 minutes total.
Equipment Needed
1. Chef’s knife, sharp (you’ll need it for thin, even onion slices)
2. Cutting board, a roomy one so you dont crowd the onions
3. Medium pot, 3 to 4 quart, where the soup will simmer
4. Wooden spoon or silicone spatula, for gentle stirring
5. Measuring spoons, for butter, garlic powder, sesame oil and salt
6. Measuring cup, for the 6 cups of broth or dashi
7. Fine mesh skimmer or slotted spoon, to remove foam and bits for a clear broth
8. Ladle and soup bowls, for serving and garnishing with scallions
FAQ
Japanese Clear Onion Soup Recipe Substitutions and Variations
- 6 cups low sodium chicken broth (or dashi) → vegetable broth or mushroom broth. Good if you want it vegetarian, and mushroom broth gives a nice umami punch, though it’s a little earthier than dashi.
- 2 tablespoons tamari or soy sauce → coconut aminos. Less salty and gluten free, with a slightly sweeter, tangy taste. Use a bit more if you like stronger flavor because it’s milder.
- 1 tablespoon mirin → 1 teaspoon rice vinegar plus a pinch of sugar. This gives the mild sweet-acid balance mirin adds, just stir the sugar in so it dissolves. Omit the sugar for a strict keto version.
- 1 tablespoon unsalted butter → 1 teaspoon neutral oil plus 1/4 teaspoon vegan butter or a little more sesame oil. Keeps richness without dairy, but watch the sesame oil cause it can be strong, so add slowly.
Pro Tips
1. Caramelize the onions gently longer than the recipe says for deeper flavor but keep the heat low so they dont brown and cloud the broth; stir more often near the end so they soften evenly and you avoid hot spots.
2. Use a splash of dashi or a tiny bit of anchovy or bonito flakes if you want umami without adding salt; steep them in the hot broth for a few minutes then strain out. It gives richness without overpowering.
3. Taste before adding salt because tamari can sneakily add a lot; if the soup feels flat, a tiny squeeze of lemon or rice vinegar brightens it up instead of more salt.
4. Make ahead and refrigerate overnight if you can, the flavors meld and the soup gets better next day. Reheat gently and skim any fat or foam that rises so it stays clear and pretty.
Japanese Clear Onion Soup Recipe
I cracked the secret to a light, restaurant-style Japanese clear onion soup that uses just nine ingredients, is ready in 30 minutes, and stays perfectly gluten-free, low-carb, keto, paleo and Whole30 friendly.
6
servings
91
kcal
Equipment: 1. Chef’s knife, sharp (you’ll need it for thin, even onion slices)
2. Cutting board, a roomy one so you dont crowd the onions
3. Medium pot, 3 to 4 quart, where the soup will simmer
4. Wooden spoon or silicone spatula, for gentle stirring
5. Measuring spoons, for butter, garlic powder, sesame oil and salt
6. Measuring cup, for the 6 cups of broth or dashi
7. Fine mesh skimmer or slotted spoon, to remove foam and bits for a clear broth
8. Ladle and soup bowls, for serving and garnishing with scallions
Ingredients
2 large yellow onions, thinly sliced (about 4 cups sliced)
6 cups low sodium chicken broth (or dashi for a more authentic flavor)
2 tablespoons gluten free tamari or soy sauce (use tamari to keep it gluten free)
1 tablespoon mirin (optional if you want a touch of sweet, omit for strict keto)
1 tablespoon unsalted butter
1 teaspoon garlic powder
1 teaspoon toasted sesame oil
salt to taste (start with 1/2 teaspoon)
2 green onions (scallions), thinly sliced for garnish
Directions
- Slice 2 large yellow onions thinly so you get about 4 cups sliced, dont rush this part it makes the soup.
- Melt 1 tablespoon unsalted butter in a medium pot over medium low heat.
- Add the sliced onions and cook gently, stirring every few minutes, until they're soft and translucent about 12 to 15 minutes. dont let them brown too much or the broth wont be clear.
- Stir in 1 teaspoon garlic powder and 1 teaspoon toasted sesame oil, cook 30 seconds to wake up the flavors.
- Pour in 6 cups low sodium chicken broth or use dashi for a more authentic flavor, then add 2 tablespoons gluten free tamari or soy sauce and 1 tablespoon mirin if using.
- Bring to a gentle simmer, reduce heat and let it simmer uncovered for 10 minutes, skim any foam or bits that rise so the soup stays clear.
- Taste and add salt starting with 1/2 teaspoon, then adjust to your liking. remember tamari can be salty so taste first.
- Remove from heat and let sit a minute, the flavors will settle.
- Ladle into bowls, garnish with thinly sliced green onions and an extra drop of sesame oil if you like.
- Serve hot with rice or enjoy on its own, this makes about 4 servings and takes around 30 minutes total.
Notes
- Below you’ll find my best estimate of this recipe’s nutrition facts. Treat the numbers as a guide rather than a rule—great food should nourish both body and spirit. Figures are approximate, and the website owner assumes no liability for any inaccuracies in this recipe.
Nutrition Facts
- Serving Size: 354g
- Total number of serves: 6
- Calories: 91kcal
- Fat: 2.7g
- Saturated Fat: 1.3g
- Trans Fat: 0.02g
- Polyunsaturated: 0.28g
- Monounsaturated: 0.78g
- Cholesterol: 5mg
- Sodium: 533mg
- Potassium: 246mg
- Carbohydrates: 12.2g
- Fiber: 1.8g
- Sugar: 6g
- Protein: 2.8g
- Vitamin A: 30IU
- Vitamin C: 8.3mg
- Calcium: 40mg
- Iron: 0.55mg
