In a large skillet, combine meat with cinnamon, lemongrass, curry leaves, garlic, ginger, onion, vinegar, salt and water. Cook over medium heat until the water has evaporated. Then add oil and stir fry the beef for about 3 minutes. Add curry powder and chili powder and cook for 3 minutes. Add more oil if necessary. Add coconut milk and simmer for 5 minutes.