Preheat your oven to 400°F (200°C).
In a large mixing bowl, combine the olive oil, soy sauce, honey, rice vinegar, minced garlic, ground ginger, salt, and pepper. Whisk until well mixed.
Add the chicken thighs to the bowl and coat them thoroughly in the marinade. Allow the chicken to marinate for at least 5 minutes while you prepare the vegetables.
On your sheet pan, arrange the sliced bell peppers, red onion, and pineapple chunks in a single layer.
Remove the chicken from the marinade (reserving the marinade) and place the chicken thighs on top of the vegetables on the sheet pan.
Pour the reserved marinade over the chicken and vegetables evenly.
Bake in the preheated oven for 25-30 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C). The vegetables should be tender and slightly caramelized.
If desired, broil for 2-3 minutes at the end to add a golden color.
Remove from the oven and let it rest for 5 minutes. Garnish with fresh cilantro if desired before serving.