Sumashijiru (Clear Soup) with Wakame and Onion
すまし汁(わかめ・玉ねぎ) · Sumashijiru
By Aoi, licensed nutritionist · From a Japanese preschool lunch menu
Sumashijiru is the clear, lightly seasoned soup that sits alongside miso soup as one of the two everyday soups of Japanese home and school cooking. Instead of miso, the dashi is seasoned with just a little soy sauce and salt, so the gentle flavor of the stock comes through. Here it is paired with soft, sweet simmered onion and tender wakame seaweed - both cut small so they are easy for little mouths to manage. In preschool kitchens, a clear soup like this is a reliable way to round out a lunch tray with vegetables and warmth without adding much salt.
Wheat-free, but uses soy sauce (made with wheat). Japanese school-lunch allergy menus usually allow it, so check with your doctor. How to read the labels
Added. Open the recipe helper (bottom right) → ☰ Menu → 🛒 Shopping list to see the ingredients for your family size.
Printing uses the number of adults and children set under Ingredients, so set those first.

Ingredients
Amounts for 1 child (1 serving). An adult counts as 2 servings.
One serving here is 1.5× the portion served to a child in a Japanese preschool, sized for Western appetites. An adult counts as two servings. Tap an ingredient to check it off.
Ingredients
- 0.5 gdried cut wakameSmall pieces of dried wakame seaweed that rehydrate in a few minutes and are used in soups and salads. Substitute: Any dried seaweed for soup, or omit.
- 15 gonion
Seasonings
- 150 gdashi stockJapanese soup stock, usually made from kombu (dried kelp) and/or bonito flakes; the base of most Japanese soups and simmered dishes. Substitute: Instant dashi granules dissolved in water, or a mild unsalted chicken or vegetable stock.
- 0.8 gsoy sauce
- 0.2 gsalt
About the Japanese ingredients in this recipe
- dried cut wakame (カットわかめ)
- Small pieces of dried wakame seaweed that rehydrate in a few minutes and are used in soups and salads. Substitute: Any dried seaweed for soup, or omit.
- dashi stock (だし汁)
- Japanese soup stock, usually made from kombu (dried kelp) and/or bonito flakes; the base of most Japanese soups and simmered dishes. Substitute: Instant dashi granules dissolved in water, or a mild unsalted chicken or vegetable stock.
Directions
- 1
Rehydrate the wakame in water and chop it finely. Cut the onion into thin slices, then cut the slices in half to shorten them.
- 2
Put the dashi stock and onion in a pot and bring to a boil. Once boiling, add the wakame and simmer.
- 3
When the onion is soft, add the soy sauce and salt and adjust the seasoning.
Nutrition
| Per | 1 serving | 1 adult serving | Your total |
|---|---|---|---|
| Energy | 9 kcal | 18 kcal | 9 kcal |
| Protein | 0.8 g | 1.5 g | 0.8 g |
| Fat | 0 g | 0 g | 0 g |
| Carbohydrates | 1.8 g | 3.6 g | 1.8 g |
| Fiber | 0.5 g | 0.9 g | 0.5 g |
| Salt equivalent | 0.6 g | 1.2 g | 0.6 g |
| Calcium | 12 mg | 24 mg | 12 mg |
| Iron | 0 mg | 0 mg | 0 mg |
| Potassium | 121.5 mg | 243 mg | 121.5 mg |
| Energy | Protein | Fat | Carbs | Fiber | Salt equiv. | Calcium | Iron | Potassium | |
|---|---|---|---|---|---|---|---|---|---|
| 1 serving | 9 kcal | 0.8 g | 0 g | 1.8 g | 0.5 g | 0.6 g | 12 mg | 0 mg | 121.5 mg |
| 1 adult serving | 18 kcal | 1.5 g | 0 g | 3.6 g | 0.9 g | 1.2 g | 24 mg | 0 mg | 243 mg |
Values are per serving (1.5× the Japanese preschool portion); an adult serving is double. They were calculated by a licensed Japanese nutritionist using the Standard Tables of Food Composition in Japan. "Salt equivalent" is sodium × 2.54, the standard Japanese measure. Allergen flags cover egg, milk and wheat only and come from the nutritionist's records. Soy sauce and miso are made with wheat but are usually allowed on Japanese wheat-free school menus, so check with your doctor.





