The classic Japanese Clear Clam Soup is made with kombu dashi broth and Manila clams. This light flavorful soup takes only a few ingredients and 15 minutes to prepare. It’s traditionally served for Girls’ Day (Hinamatsuri).
Although Japanese restaurants outside of Japan serve miso soup with just tofu and wakame seaweed, there are many variations of miso soup in Japan and we also have some soups that do not contain miso.
As Japan is surrounded by the ocean, we have abundant fresh seafood to enjoy with our soups. Today’s recipe, Japanese Clear Clam Soup (Ushio-jiru) (あさりの潮汁) is one of the classic soups enjoyed throughout Japan.
Ushio-Jiru – Japanese Clear Clam Soup
Ushio-Jiru (潮汁) is a clear soup made with seafood such as white fish or clams and seasoned with only salt and sake.
“Clear broth” or Sumashi-jiru (すまし汁) doesn’t mean it’s plain water. For Japanese clear broth, we use various dashi broth, made from kombu or a combination of kombu and katsuobushi.
When we use clams in the soup, we want to make sure the flavors coming from the clams is the prominent one. Therefore, we use the dashi broth that has the most subtle flavor – Kombu Dashi.
The most commonly used Awase Dashi made with kombu and katsuobushi (dried bonito flakes) is a bit too strong and it might ruin the flavors coming from the clams, so I wouldn’t recommend using it.
Use Fresh and Good Quality Ingredients
As the recipe is so simple, I can’t stress enough that the quality of ingredients and attention to detail for cooking this soup does matter.
Use fresh clams as they are flavorful and succulent. It’s very important to de-grit clams so your soup won’t eat any sands or grits that might be off-putting. I have a detailed guide on how to de-grit clams (Japanese way). You’ll be surprised how much stuff comes out from so-called “ready-to-use” clams you purchased from the store.
Other important ingredients are a small piece of kombu and a little splash of sake. The little piece of kombu has so much umami in there that you should extract the flavors slowly (pre-soaking and slowly heating up).
Try tasting the soup before and after adding sake. Sake is made with fermented rice and it has umami and sweetness in there while masking the unwanted smell that sometimes accompanies seafood. After adding sake, don’t you feel the essence of the broth sharpens up? It’s a bit hard to describe, but the Japanese believe the magic in sake and the big difference it makes with a dish.
Japanese Clear Clam Soup for Girls’ Day
As many of you already know, clear clam soup is a signature dish to serve on Girls’ Day (Hinamatsuri), which is on March 3rd in Japan. The soup is usually served with Chirashi Sushi, colorful sushi with ingredients scattered on top of seasoned sushi rice. Some sweets like Sakura Mochi and Hanami Dango are served as well. Please read more about this custom here.
Japanese Clear Clam Soup (Ushio-jiru)
After You Bought Clams…
- After you purchase manila clams, you will need to de-grit (mostly inactive time for 1 hour). Even though they are “ready to use”, I highly recommend doing this process. Please see my How to De-Grit and Clean Clams post.
To Cook Clams
- Gather all the ingredients.
- Put water, kombu, and clams in a saucepan and start cooking on medium heat. If you have extra time, I recommend adding kombu in water first to let it steep for a longer time.
- When small bubbles are around the edges of the pot and water is almost boiling, discard the kombu. You can also skim the foam to make a very nice clear broth. When boiling, turn down the heat.
- When all the clams open up, add sake. Taste the soup and add a pinch of kosher salt if needed. The clams will get chewy and hard when you cook for a long time, so turn off the heat and serve.
- Keep the leftovers in an airtight container and store in the refrigerator for 2-3 days.