Boiled eggs are delicious when eaten with salt, but you can experience a distinctive flavor with Nitamago. Japanese seasonings give the egg whites a rich taste that complements the yolks well. This dish is also known as 'ajitama' or 'ramen eggs.'
Fill a large pot with plenty of water and bring it to a boil. Once boiling, reduce the heat to medium and carefully lower the eggs, which should be taken directly from the refrigerator, one at a time using a slotted spoon or ladle. Let them cook for 7 minutes or for your preferred duration.
After cooking, promptly cool the eggs in ice water or under running water to minimize residual heat. Then, peel off the shells.
Mix seasonings (sake, mirin, sugar, and soy sauce) in a small pot and bring it to a boil. Once boiling, turn off the heat and let the mixture cool down. It is more efficient to start preparing while the eggs are cooking.
Place the boiled eggs and the seasoning mixture in a ziplock bag and seal it, removing as much air as possible. Let them sit in the refrigerator for 2 hours. (The longer you let them soak, the stronger the flavor will be.)