Boil water in a pan, add a pinch of salt, and cook nanohana for 1–2 minutes. Drain and rinse under cold water, then squeeze out excess water.

Separate the nanohana florets and chop the remaining stems roughly.

Mix sugar, salt, and vinegar in a bowl to prepare sushi vinegar.

In another bowl, mix egg, sugar, and a pinch of salt to prepare the egg mixture.

Heat half the salad oil in a pan, add the egg mixture, and stir with chopsticks over medium heat until crumbly. Remove from heat.

Wipe the pan clean, heat the remaining salad oil, and stir-fry the beef over medium heat.

Add yakiniku sauce to the beef and stir-fry until the liquid evaporates.

In a large bowl, mix cooked rice with sushi vinegar using a cutting motion.

Add chopped nanohana, scrambled egg, and sesame seeds to the rice and mix well to make sushi rice.

Place a piece of plastic wrap, add nanohana florets, beef, and a portion of sushi rice. Wrap and shape into a ball. Repeat for 10 servings.