Cut chicken thighs into about 1 inch cubes
Add soy sauce, ground ginger, black pepper, kosher salt, and olive oil to chicken
Sprinkle in cornstarch and all purpose flour and toss to coat
Spread chicken on a foil-lined sheet tray
Bake at 500°F for 20-30 minutes
While chicken cooks, rough chop onion, red bell pepper, and yellow bell pepper
Toss vegetables with oil, salt, and pepper
Add vegetables to oven for about 10 minutes
After 10-15 minutes, stir chicken pieces and lay flat, return to oven for another 10 minutes
Combine ketchup, white distilled vinegar, white sugar, and pineapple juice in a saucepan
Heat sauce over medium to low heat and simmer until sugar dissolves
Add about ½ cup sauce to chicken pan and mix to coat
Return to 500°F oven for 1-2 minutes until sauce simmers and coats chicken
