Place eggs in a pot and cover with 1 inch of water.

Remove eggs and stir 1 teaspoon of white vinegar into the water.

Bring the water to a boil.

Gently place eggs back into the boiling water.

Cover and cook for 5 minutes for soft-boiled eggs or 8 minutes for hard-boiled eggs.

Prepare an ice bath while the eggs are cooking.

Remove the pot from heat and immediately transfer the eggs to the ice bath.

Peel the eggs carefully.

Combine 1/2 cup reduced-sodium soy sauce, 1/4 cup prepared ponzu sauce, 1/4 cup mirin, 2 tablespoons chopped scallions, 1 clove roasted garlic, 1/2 teaspoon light brown sugar, 1/2 teaspoon sesame oil, 1/2 teaspoon togarashi, and 1/2 teaspoon grated fresh ginger in a jar or container.

Mix well to dissolve the sugar and break up the garlic.

Place the peeled eggs in the mixture.

Seal the container and marinate in the refrigerator for 1 day (24 hours).

Eggs can be stored for 3-4 days after marinating.