Chop mitsuba into 1cm pieces, place in a microwave-safe container, add 2 tsp water, cover loosely with plastic wrap, and microwave at 600W for 30 seconds. Rinse with water and squeeze out excess moisture.

Heat butter in a frying pan, add fresh salmon fillet, cook until browned, flip, cover with a lid, and cook on low heat for 5 minutes.

Let the salmon cool slightly, then remove bones and skin while flaking the meat.

In a bowl, combine warm cooked rice, flaked salmon, salt, pepper, and soy sauce. Mix thoroughly.