Creating Japanese Chicken Yakitori is straightforward if you follow these simple steps:

1. Prepare the Marinade: In a bowl, whisk together soy sauce, sake, mirin, brown sugar, and sesame oil until the sugar dissolves.
2. Cut the Chicken: Cut the chicken thighs into bite-sized pieces, about 1 to 1.5 inches.
3. Marinate the Chicken: Place the chicken pieces in the marinade. Cover and refrigerate for at least 30 minutes.
4. Prepare Skewers: While the chicken is marinating, soak bamboo skewers in water to prevent burning on the grill.
5. Skewer the Chicken: Thread the marinated chicken pieces and green onion pieces onto the soaked skewers, alternating between chicken and green onions.
6. Preheat the Grill: Preheat your grill to medium-high heat.
7. Grill the Skewers: Place the skewers on the grill. Cook for about 3-4 minutes on each side, brushing with leftover marinade for extra flavor.
8. Check for Doneness: Ensure the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
9. Remove and Rest: Once cooked, remove the skewers from the grill and let them rest for a few minutes.
10. Garnish and Serve: Sprinkle sesame seeds on top before serving.

These steps will guide you in creating this incredible dish effortlessly.