To best answer that, first allow me to explain what “shoyu” is. Shoyu means soy sauce. Though it’s a Japanese word, it’s what they commonly call soy sauce in Hawaii, which is why “shoyu chicken” is often considered Hawaiian cuisine. Hawaiian shoyu chicken is a popular dish. Chicken thighs are simmered in shoyu. Sugar is traditionally added to the sauce to give it a sweeter taste, otherwise, the saltiness from the shoyu can be overbearing. It is similar to teriyaki chicken but it is simmered in the sauce, not grilled or baked. The chicken shreds off the bone more easily than teriyaki chicken and is more tender.