Soak hijiki seaweed in plenty of water until rehydrated, then drain. Mince the onion and microwave it uncovered at 600W for 30 seconds, then let it cool.

In a bowl, mix ground meat with salt and pepper until sticky. Add hijiki and minced onion, then mix thoroughly. Divide into 4 portions and shape into oval patties.

Coat each patty lightly with flour, then dip into beaten egg and coat with breadcrumbs.

Heat cooking oil to 160°C in a pot, then fry the patties for 3–4 minutes without moving them until the breadcrumbs set. Flip and fry both sides until golden brown and cooked through, about 3–4 minutes per side.