For the Meatballs:

• 2 pounds ground beef
• 1 cup breadcrumbs
• 1 large onion (shredded or finely chopped)
• 2 large eggs
• ½ teaspoon garlic powder
• Salt and pepper (to taste)

For the Sweet and Sour Sauce:

• 3 tablespoons rice vinegar
• ⅓ cup brown sugar (packed)
• 1 cup chicken broth (low sodium)
• ⅓ cup ketchup
• 1 tablespoon tomato paste
• ¼ cup pineapple juice (from canned pineapple)
• ½ teaspoon cornstarch
• 1 teaspoon salt

For the Stir-Fry:

• 1 tablespoon vegetable oil
• 1 large onion (diced)
• 2 cloves garlic (minced)
• 1 medium red bell pepper (cut into 1-inch pieces)
• 1 medium green bell pepper (cut into 1-inch pieces)
• ½ cup pineapple chunks