01 - Bring a pot of water to a full rolling boil over high heat.
02 - Gently lower the eggs into the boiling water using a spoon. Boil for exactly 7 minutes to achieve a slightly runny yolk consistency.
03 - Prepare an ice bath in a bowl. Immediately transfer the cooked eggs to the ice bath and let cool for 5 minutes to stop the cooking process.
04 - Carefully peel away the eggshells while maintaining the egg shape.
05 - In a zip-top bag or small container, combine soy sauce, water, mirin, and sugar. Mix thoroughly until the sugar completely dissolves.
06 - Place the peeled eggs into the marinade, ensuring they are fully submerged. Seal the container or bag.
07 - Marinate in the refrigerator for at least 4 hours, preferably overnight. Turn the eggs occasionally to ensure even coloring and flavor distribution.
08 - Remove the eggs from the marinade, slice in half, and serve atop ramen noodles, rice bowls, or enjoy as a standalone snack.