Skillet Sweet and Sour Chicken

Ingredients

• 3 tablespoons all-purpose flour
• ½ teaspoon garlic powder
• ½ teaspoon salt
• ½ teaspoon ground black pepper
• 1 pound skinless (boneless chicken breast halves, cut into 1-inch cubes)
• 3 tablespoons vegetable oil (divided)
• 3 celery ribs (sliced)
• 2 green bell peppers (diced)
• 1 onion (chopped)
• ½ cup ketchup
• ½ cup lemon juice
• ½ cup crushed pineapple with syrup
• ⅓ cup packed brown sugar