Step 1

Place eggs in a pot. Cover with about 1 inch water. Remove eggs and stir vinegar into the water. Bring to a boil. Gently place eggs back in. Cover and cook for 5 minutes to soft-boil. Cook 3 minutes more for hard-boiled eggs. Prepare an ice bath in the meantime.

Step 2

Remove heat heat and immediately place eggs in the ice bath. Peel eggs carefully.

Step 3

Combine soy sauce, ponzu sauce, mirin, scallions, garlic, brown sugar, sesame oil, togarashi, and ginger in a container such as a jar. Mix well to ensure the sugar dissolves and the garlic breaks up.

Step 4

Place eggs in the mixture and seal. Marinate for 1 day. Eggs keep for 3 or 4 days after.