Filipino Chicken Sopas
1 pinch salt and ground black pepper to taste 1 pound bone-in chicken thighs, skin removed 1 teaspoon garlic powder 1 teaspoon onion powder 2 carrots, diced 2 tablespoons fish sauce, or more to taste 3 tablespoons butter 4 teaspoons chicken bouillon granules 6 cups water, or more as needed ½ (16 ounce) package elbow macaroni ½ cup evaporated milk ½ onion, chopped ½ teaspoon ground black pepper