Cut the frozen yellowtail into block-shaped pieces, blanch them in boiling water for about 10 seconds, and then transfer them to cold water. Wipe dry with kitchen paper and cut into approximately 1cm (0.4 inches) wide pieces.
Trim the roots of the kaiware radish sprouts and cut them into thirds.
Cut the dashimaki tamago into small pieces of slightly less than 1cm (0.4 inches).
In a bowl, combine the yellowtail and marinade ingredients, mix well, and let it marinate in the refrigerator for 5-10 minutes.
Mix the sauce ingredients together and place in a separate sauce dish.
Serve the rice in bowls and arrange the marinated yellowtail, dashimaki tamago, and kaiware radish sprouts evenly. Top with flying fish roe, sprinkle white sesame seeds, and serve with the sauce on the side.
