Sieve the boiled yolks through a medium mesh strainer. In a small nonstick pan, combine the yolks, sugar and salt, then cook over low heat until yolks become dry, 6-7 minutes. Stir often taking care not to let burn. Set aside.
In another nonstick pan over low heat, cook Katsuobushi and Soy Sauce until dry, about 5 minutes, stirring often. Add sesame seeds and cook another minute.
Combine all together in a bowl. Add Nori and Aonori. Mix well.