2 lbs boneless skinless chicken breasts (cut into chunks)

2 tbsp cornstarch

1 tbsp soy sauce

1/2 tsp salt

1/4 tsp black pepper

1 tbsp vegetable oil

1 cup pineapple juice

1/2 cup brown sugar

1/2 cup rice vinegar

1/3 cup ketchup

3 tbsp soy sauce

1 tsp minced garlic

1/2 tsp grated ginger (optional)

1 red bell pepper (chopped)

1 green bell pepper (chopped)

1 small onion (chopped)

1 cup pineapple chunks

1 tbsp cornstarch + 2 tbsp water (optional)

Cooked rice or noodles (for serving)

Green onions and sesame seeds (for garnish)