1. Preheat oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.

2. In a medium bowl, whisk together pineapple juice, soy sauce, brown sugar, rice vinegar, ginger, garlic, and sesame oil to make the marinade.

3. Place chicken cubes in a large bowl or zip-top bag. Pour half of the marinade over the chicken and toss to coat. Marinate for 15–20 minutes.

4. Meanwhile, chop the bell peppers, red onion, and pineapple into 1-inch pieces and place them in a large mixing bowl.

5. Add marinated chicken to the bowl of vegetables and pineapple. Pour in remaining marinade and toss until well coated.

6. Spread the chicken, vegetables, and pineapple in a single, even layer on the prepared sheet pan. Avoid overcrowding.

7. Roast in the preheated oven for 20–25 minutes, stirring halfway through, until the chicken is cooked through and vegetables are tender-crisp.

8. For more caramelization, broil on high for 2–3 minutes at the end, watching closely to prevent burning.

9. Remove from oven and let rest for a couple of minutes. Garnish with green onions and sesame seeds if desired.

10. Serve hot over white rice, brown rice, quinoa, or cauliflower rice for a complete meal.