Creating Baked Sweet and Sour Chicken is simple when you follow these steps:

1. Preheat the Oven: Set your oven to 375°F (190°C) and prepare a baking dish by greasing it lightly.
2. Prepare Chicken: In a large bowl, combine the chicken pieces, garlic powder, ginger powder, salt, and pepper. Toss to coat evenly.
3. Mix the Sauce: In a separate bowl, stir together the sweet and sour sauce, soy sauce, and cornstarch until well combined.
4. Combine Ingredients: Add the chopped bell peppers, pineapple chunks, onion, and the sauce mixture to the chicken. Toss everything to ensure the chicken and vegetables are well coated with the sauce.
5. Transfer to Baking Dish: Pour the mixture into the prepared baking dish, spreading it evenly.
6. Bake: Place the dish in the preheated oven and bake for 35-40 minutes, or until the chicken is cooked through and the vegetables are tender.
7. Stir Occasionally: Halfway through baking, stir the mixture to ensure even cooking and flavor distribution.
8. Check for Doneness: Ensure the chicken reaches an internal temperature of 165°F (74°C) before removing it from the oven.
9. Serve: Once done, remove the dish from the oven and let it cool for a few minutes before serving over rice.

These straightforward steps will guide you through creating this incredible dish with ease!