Chicken Nanban with Tartar Sauce

In a large bowl, combine soy sauce, mirin, rice vinegar, sugar, grated ginger, and minced garlic. Mix well.

Add the chicken pieces to the marinade and ensure they are well coated. Marinate for at least 15 minutes, or up to 30 minutes in the refrigerator.

While the chicken is marinating, prepare the tartar sauce. In a separate bowl, combine mayonnaise, finely chopped hard-boiled egg, finely chopped onion, pickled relish, lemon juice, salt, and pepper. Mix well and set aside.

In a shallow dish, combine all-purpose flour and potato starch. Mix well.

Remove the chicken pieces from the marinade and dredge them in the flour mixture, ensuring they are fully coated. Dip the dredged chicken into the beaten egg, and then dredge again in the flour mix. This double coating is key.

Heat vegetable oil in a deep fryer or large pot to 350°F (175°C).

Carefully add the chicken pieces to the hot oil in batches, being careful not to overcrowd the pot. Fry for 4-5 minutes per batch, or until golden brown and cooked through.

Remove the fried chicken from the oil and place them on a wire rack to drain excess oil.

Serve the Chicken Nanban immediately with a generous dollop of tartar sauce.