Start by beating the eggs in a bowl gently, try and make sure that the eggs do not froth up at all. You can also start soaking your shiitake mushrooms in water while you are preparing the next few steps.

In a separate bowl, mix together the dashi stock, soy sauce, sake, salt and sugar. Add this mix to the egg while stirring constantly to get a good mix. Once you have mixed everything together, strain the mix through a very fine sieve to make sure that the mixture is perfectly smooth.

Remove the shiitake mushrooms from the water, remove the stems and slice in half. Add two of the sliced halves of shiitake, one large prawn and two slices of kamaboko to a small cup or bowl for each person. Divide the custard among four 6-oz. ramekins and fill the cups with the egg mixture to near the top.

Preheat your steamer, add the cups to it and steam them on a low heat for approximately 15 minutes. Alternatively set the cups inside a 9-by-13-inch baking dish, and set the baking dish in the oven set at 325. Pour enough boiling water into the baking dish to come halfway up the sides of the ramekins and bake the custards until set but still slightly loose in the center, about 30 minutes. You can poke a toothpick in the Chawanmushi to check if it has set. If the toothpick still has egg mix on it, allow them to steam for a little longer. Set the cups on to a baking rack so that they can cool slightly before serving
Serve as an appetizer to any traditional Japanese meal.

‍

‍

Source: saveur.com