Stir-Fried Chicken with Holy Basil

Ingredients:
2 tablespoons vegetable oil
2 garlic cloves, crushed
8 ounces chicken breast, boned and chopped in small pieces
2 big red chiles, chopped finely
2 handfuls of holy basil (bai krapao)
2 tablespoons fish sauce
1 tablespoon sugar
2 tablespoons water or chicken stock