Step 1

Fill a medium saucepan with water and bring to a boil over high heat. Reduce the heat to medium so that the water is simmering just below the boil. Gently lower the eggs into the water using a slotted spoon.

Step 2

Let the eggs simmer for 6 ½ minutes.

Step 3

While the eggs are simmering, place several ice cubes in a bowl large enough to hold all of the eggs. Add cold water to cover.

Step 4

When the eggs are finished cooking, pour off the hot water and run cold water of them for a few minutes to cool them down. Transfer the eggs to the ice bath and let them sit until they are completely cooled, about 5 minutes. Drain.

Step 5

Carefully peel the eggs.

Step 6

In a medium saucepan, combine the soy sauce, sake, mirin, water, sugar, and ginger and bring to a boil over high heat. Reduce the heat to medium-low and simmer, stirring frequently, until the sugar dissolves completely, about 3 minutes.

Step 7

Transfer the mixture to a jar or container large enough to hold both the marinade and the eggs and let cool to room temperature, about 20 minutes.

Step 8

Add the peeled eggs to the soy sauce mixture, cover, and refrigerate for about 8 hours (it is not ideal to leave them longer than 12 hours as the texture of the eggs may begin to suffer).

Step 9

Remove the eggs from the marinade and store them, covered, in a bowl in the refrigerator for up to 3 days.