Dashi (Japanese stock) is the backbone of Japanese cuisine, particularly soups, simmered dishes and dipping sauces served with noodles. Yet, compared to other Japanese ingredients, such as tamari, miso, rice vinegar, or sake, dashi has been rather overlooked. 

So, in this post I dive into what dashi is, what types of dashi are the most popular, how to make dashi, and how to use it in recipes..

What is Dashi

Dashi is a Japanese stock that has a very rich and complex flavor yet is very quick and easy to prepare. It can be made in less than 15 minutes and usually contains only one or two ingredients (plus water). How is it possible?

The answer is glutamate (MSG). All the dried ingredients that are used to make Japanese soup stock are rich in naturally occurring glutamate and provide intense flavor to the stock. With a distinctive sweet and savory note, the deep umami flavor is what sets dashi apart from other stocks. In other words, dashi is the embodiment of umami. 

To understand how dashi plays such a successful role in imparting flavor, it is important to understand umami synergy. Even if you don’t like science, this is actually really fascinating. Umami synergy involves the relationship between umami-causing glutamate and nucleotides. Nucleotides do not cause umami on their own. But when present alongside glutamate, they are capable of amplifying the umami taste 15 fold! Not only is the umami taste magnified, it is more sustained and longer lasting, too. 

What does it have to do with dashi? To explain that, let’s first explore the various types of dashi.

Types of Dashi

There are five different types of dashi:

• Kombu dashi: perhaps the simplest dashi and also the easiest to prepare as it only contains kombu (dried sea kelp). It has a mild flavor and is typically used when the flavor of other ingredients is mild. 
• Shiitake dashi: another plant-based dashi made with a single ingredient – dried shiitake mushrooms. Shiitake dashi has a quite strong mushroom flavor and is usually combined with kombu dashi (one part shiitake dashi with two parts kombu dashi).
• Iriko/Niboshi dashi: seafood-based stock made from iriko (dried baby anchovies or sardines). It has a strong fishy aroma and flavor.
• Katsuo/Bonito dashi: seafood-based stock made from katsuobushi (dried and fermented skipjack tuna/bonito that is shaved into thin flakes). It is aromatic, flavorful, and since katsuobushi doesn’t need to be soaked (compared to kombu, shiitake, and iriko), it is the fastest dashi to prepare.
• Awase/Ichiban dashi: the most common, all-purpose dashi and what most people know as simply, dashi. It is made with a combination of kombu (dried kelp) and katsuobushi (dried bonito flakes). Awase has a more complex and rounded flavor than any of the dashi above. 

Now, back to the umami synergy. Kombu is rich in glutamate. Dried shiitake mushrooms and katsuobushi are very rich in nucleotides. So, combining kombu with shiitake mushrooms or kombu with katsuobushi makes perfect sense as it results in such an intense umami flavored dashi stock.

Tips for Making Kombu Shiitake Dashi

Ingredients

Kombu shiitake dashi is the most common vegetarian/vegan dashi. It is incredibly flavorful yet it only calls for two ingredients:

• Kombu: there are many variants of kombu and some are richer sources of glutamate than others. These are classified into different categories based on where the kombu is grown as well as physical characteristics of the seaweed and how old the kombu is. If you are lucky enough to have numerous varieties to choose from, ma-kombu js the highest in glutamate (hidaka-kombu is the lowest). Also, the older the kombu the better as the stronger ‘marine’ flavors tend to fade over time in favor of the rich and savory ones. If you can afford it, don’t be afraid to pay a little bit more for the best kombu you can get. You get a lot of flavor from a very small mass of kombu, and its effect on the flavor of your final dish is undeniable.
• Shiitake mushrooms: the most important thing is to use dried shiitake mushrooms. Fresh shiitake mushrooms don’t have the same deep and intense flavors as the dried ones. There are three types of shiitake mushrooms, depending on how the cap is formed.
  1. Donko: highest grade of shiitake mushrooms with thick, domed caps. 
  2. Kouko: somewhere between Donko and Koshin – not as thick and domed as Donko but not as thin and flat as Koshin.
  3. Koshin:  lowest grade of shiitake mushrooms with thin, flat caps. 

How to Make Kombu Shiitake Dashi

Although there are many differences in the way people make dashi, the fundamentals are always the same – infusing water with dried ingredients rich in glutamate. 

1. Clean the shiitake mushrooms. Before proceeding with the recipe, check if there is any dirt or debris trapped under the gills of the mushrooms. If there is, use a mushroom brush to remove it. Do not wash the mushrooms.
2. Soak the kombu and shiitake mushrooms. Add a piece of kombu and shiitake mushrooms into a mason jar. Fill the jar with cold water and screw the lid on to keep the mushrooms completely submerged. It is best to use cold water to slowly bring out the flavor from mushrooms. The mushrooms will float to the top. So, if you need just a little bit of dashi (not an entire mason jar), put something heavy on top of the mushrooms, so they stay submerged and fully re-hydrate. Let the kombu and shiitake mushrooms soak for at least a few hours, ideally overnight.
3. Strain the dashi. Pour the soaking liquid into a jar (or a bowl) over a fine mesh strainer. Then squeeze the shiitake mushrooms over the jar.

Note: you can also prepare kombu shiitake dashi using a heating method, which yields a stronger-tasting stock.

How to Use Dashi

Dashi is used in any Japanese dish that requires liquid for cooking. Some of the most popular dishes with dashi include:

• Miso soup: the base of traditional miso soup is a simple combination of dashi and miso (fermented bean paste). Combined with tofu, scallions, and seaweed, this soup brings a comforting savory, umami flavor with a variety of textures. Honestly, miso soup is hands down my favorite soup. I can eat it any time of the day and never get tired of it.
• Ramen: like many other Japanese soups, ramen is based on dashi. Combined with ramen noodles and various toppings, ramen soup has become one of the most popular dishes in Japan in recent years. 
• Ohitashi: this typical deeply flavorful Japanese side dish is made by blanching vegetables in a dashi-based sauce. Green vegetables, particularly spinach, is the most common vegetable choice, but other vegetables can be used as well.

If you try any of these recipes, please, leave a comment and rate the recipe below. It always means a lot when you do.