Mentsuyu Recipe: How to Use and Store a Mentsuyu Soup Base

Mentsuyu, or tsuyu, is a concentrated, multipurpose Japanese soup base. When diluted, the robust base can be used as a dipping sauce for fried items, like tempura and cold noodle dishes (like somen noodles or zaru soba, with cold soba noodles), or as the foundation for hot noodle soups like ramen or udon noodles.

Like dashi stock, mentsuyu uses kombu (kelp) and katsuobushi (dried bonito flakes) to impart deep umami flavors. In place of either ingredient, mentsuyu can also be made using a dashi powder. You can make vegetarian or vegan mentsuyu by using shiitake mushrooms instead of katsuobushi.

In Japanese cooking, mentsuyu is generally understood in two categories: kaketsuyu and mentsuyu. When mentsuyu is combined with hot water to make a hot noodle broth, it’s called kaketsuyu. When mentsuyu is combined with room temperature or cool water to make a cold noodle soup broth, it’s called tsuketsuyu.

Mentsuyu is incredibly simple to make and easy to make sweeter or saltier, according to personal preference:

1. 1. Choose your dilution ratio. One of the benefits of making mentsuyu at home is that you can control the base’s flavor intensity, which varies based on the dish. When choosing a dilution ratio, a general starting point is three parts water to 1 part mentsuyu.
2. 2. Use it as a seasoning or condiment. Concentrated mentsuyu sauce can also be used as a stand-in for standard soy sauce when seasoning stews, hot pot dishes (nabemono), and dipping sauce.
3. 3. Incorporate condiments. When using mentsuyu as a dipping sauce for dishes like zaru soba, you can provide additional ingredients and seasonings to mix into the dish, such as sliced scallions, wasabi, grated ginger, or daikon radish.
4. 4. Store mentsuyu in the fridge. You can store mentsuyu noodle sauce in the refrigerator in a sealed container for up to a month.