Please go through proper preparation for Wasabi flowers to unlock its unique spicy flavor.
Cut the wasabi flowers into a few centimeter-long pieces, place them in a bowl, sprinkle with sugar and salt, and rub lightly. This process transforms bitterness into spiciness.
Pour hot water (about 80°C) over the Wasabi flowers and let them soak for about 2 minutes. Drain and rinse briefly with cold water.
Place the Wasabi flowers in a sealable container, sprinkle with salt, and refrigerate for about 3 hours to enhance the spicy taste.
Take about 2 tablespoons of the prepared Wasabi flowers and mix them with cooked rice, adding a pinch of salt. Mix gently to avoid mashing the rice.
Place the seasoned rice on plastic wrap and form it into a cylindrical shape.
Arrange 3 slices of beef on plastic wrap and wrap them around the rice.
Heat a frying pan over medium heat, melt some beef tallow, and sauté the beef rolls. Lightly salt the surface and rotate them until lightly charred.
Cut the rolls into bite-sized pieces.
