Cut eggplants into chunks and soak them in salted water (600cc water + 2 tsp salt) for 10 minutes.

Drain the eggplants and pat them dry with a paper towel.

Mix ground meat, chopped onion, beaten egg, salt, and pepper in a bowl. Add the eggplant chunks and mix well.

Shape the mixture into patties and coat lightly with flour.

Heat salad oil in a pan and pan-fry the patties until golden brown on both sides.

In a separate pan, melt 1 tbsp butter and add ketchup, Worcestershire sauce, and sake. Simmer for 2–3 minutes to create the sauce.