1. Wrap the tofu with 2 layers of paper towels and place on a microwave safe plate. Microwave for about 2~3min at 600W. Let it cool to room temperature. Then put it into the food processor, process until smooth.
2. In a bowl, add the tofu, leek, garlic, tuna and all ingredients A. Mix and knead the mixture until it becomes smooth and elastic.
3. Form into patties and coat with flour. In a skillet, heat 2 tbsp oil and fry them on both sides until nicely brown and reduce the heat to low. Cover and continue cooking for about 5 more minutes or until cooked through.
4. In a small cooking pot, add all the sauce ingredients and bring to boil. Add dissolved katakuriko to thicken the sauce.