Make Marinade: Whisk together soy sauce, ketchup, brown sugar, chicken broth, ginger, garlic, and sesame oil. Pour half over the chicken to marinate for at least 2 hours. Reserve the rest.
Prep Base: Preheat oven to 400 degrees Fahrenheit. Line a baking sheet with foil. Place one thick pineapple slice down and insert two soaked wooden skewers vertically into it.
Stack: Thread the marinated chicken thighs onto the skewers tightly, pressing down. Top with another pineapple ring.
Roast: Bake for 45 minutes, brushing the stack with the reserved marinade every 15 minutes until the internal temperature reaches 165 degrees Fahrenheit.
