In a mixing bowl, combine soy sauce, mirin, sake, and sugar to make the marinade.
1/4 cup soy sauce, 2 tablespoons sake, 2 tablespoons sugar, 1/4 cup mirin
Add chicken pieces to the marinade, tossing to coat. Let it marinate for at least 30 minutes.
1 lb chicken thighs
Preheat the grill or grill pan over medium-high heat.
Thread the marinated chicken pieces and green onions onto skewers.
2 green onions
Grill the skewers for about 7-8 minutes on each side, or until the chicken is fully cooked and slightly charred.
Brush with sesame oil and season with salt and pepper before serving.
1 teaspoon sesame oil, Salt and pepper to taste
Notes
Soak wooden skewers in water for 30 minutes before grilling to prevent burning.
Serve with a side of rice and a sprinkle of sesame seeds for a complete meal.