Chawanmushi – Japanese Egg Custard

Chawanmushi is a Japanese savoury egg custard dish. Chawan means tea cup and mushi means steam, so it’s literally called “tea cup steam”. It consists of a delicate, stock-enriched egg custard mixture flavoured with soy sauce, dashi and mirin. Other ingredients are placed in the cup such as kamaboko, chestnuts, prawns, crab, chicken, ginko nuts and assorted vegetables like mushrooms, carrots and bamboo shoots. Even though the egg custard completely sets in steaming, the stock and juices released from the various other ingredients make the dish a little soupy. This dish is regarded as a soup in Japan and it is usually eaten as an appetizer.


I first had chawanmushi when we stayed at a Buddhist Temple in Mount Koysan.

Chawanmushi is easy and relatively quick to make, and it can be eaten hot or chilled. To make chawanmushi you need to make some dashi stock which is combined with egg to make a light custard that is steamed with various other ingredients. 


Dashi is essential to Japanese cooking, it provides the umami taste that is the foundation of Japanese cuisine. It is a clear, fish stock (generally made with kombu and bonito) used for soups, simmered dishes, salad dressings, and marinades. Dashi enhances all the flavours that surround it due to the kombu’s high levels of naturally occurring glutamate (think MSG). 


Basic Dashi Stock
• 6 cups water
• approx 8cm square of kombu (dried seaweed/kelp)
• 3 tablespoons dried bonito flakes


Put kombu in pot and add cold water. Soak the kombu for 30 minutes (it will soften and expand).


Bring the water and the kombu almost to a boil over medium heat (this should take around 10 minutes). Just before the water comes to boil, remove the kombu and discard. Add the dried bonito flakes to the pot, boil for 30 seconds. Turn the heat off and let steep for 5 minutes. 


Strain the stock and allow to cool.


Note: Don’t boil the kombu as it will turn slimy, and the stock will be cloudy and bitter. The dashi stock will keep for two days in the refrigerator and can be frozen.


Chawanmushi
(This recipe yields 4-6 cups, depending on the size of the cups or bowls/ramekins)


• 4 eggs
• 2 ½ cup dashi stock
• 1 ½ teaspoon salt
• 1 tablespoon soy sauce (kikkomon brand)
• 1-2 tablespoons mirin or sake (to taste)
• 2-3 dried shiitake mushrooms, soaked and thinly sliced
• 4 prawns, shell/deveined and diced, and marinated with a little salt and sake
• garnish with your choice of greens – mitsuba, watercress, coriander or spring onion


To make the custard - in a bowl, beat the eggs lightly with chopsticks (be careful not to aerate and whip in bubbles). In another bowl, mix room-temperature dashi, salt, mirin, and soy sauce (taste the stock before adding it to the egg and adjust the seasoning to desired taste). Pour stock mixture into beaten eggs. Mix well but do not beat (the surface of the mixture should be free of bubbles or foam). Strain the mixture through a fine sieve.


The seasoned stock mixture should be 3 times the volume of beaten egg, so apply this ratio of 3:1 in adjusting this recipe to the number of diners.


In each chawanmushi cup (or custard cup or ramekin) put in a few pieces of prawns and slices of shiitake mushrooms. Fill cups with custard mixture and skim off any bubbles that appear on top of the mixture, cover with a lid or foil. 

Preheat a steamer on high heat. Turn down the heat to low and place the cups in the steamer. Steam for about 15 minutes until the custard is just set. After 12 minutes, open the lids and add some greens to each cup, replace the covers and continue steaming for the remaining 3 minutes. 

The chawanmushi is done when a toothpick inserted in the center comes out clean. The custard should be set but still very soft and jiggle freely. It should have a silky, smooth texture similar to that of soft tofu.

Note: The chawanmushi needs to be steamed on a low heat because if the temperature is too high the egg protein coagulates leaving many tiny air pockets and the custard becomes tough. Also, do not overcook it and steam it for too long as the custard will be overdone and the top will be pocked and cracked, and loose its silkiness. 

Chawanmushi is so silky and light it literally melts in your mouth. The custard is very flavourful and packed with umami from the dashi and shittake mushrooms, and as you consume it, you find little bits of prawn and shitake mushrooms.


I only added shittake mushrooms and prawns to my chawanmushi but feel free to change the fillings – you can add anything that will complement the taste of the savoury custard base. Provide little surprises and varying flavours for your diners to find at the bottom of the egg custard cup!

A good chawanmshi should have a subtle flavour so do not overload the cups with too many ingredients. I recommend the addition of just 2-3 other ingredients. The additions of other ingredients should fill the cups no more than one-third of the way.