Colombian Chicken Stew (Ajiaco)

INGREDIENTS

• 1 (3 pound) whole chicken, cut into pieces
• 8 potatoes, peeled and cubed
• 1 onion, chopped
• 1 teaspoon salt
• 1 teaspoon ground black pepper
• 1/2 teaspoon garlic powder
• 1 (15.25 ounce) can whole kernel corn, drained
• 2 avocados, peeled, pitted, and diced
• 1/4 cup chopped fresh cilantro
• sour cream, for topping (optional)