Melt ghee or heat oil in a large saucepan over medium heat. When hot, add garlic, carrots, celery, onion and apple. Saute for about 5 minutes until onions start to brown. Add flour, curry powder and paste and coriander and stir to combine. Add stock and bring to a boil Add tomatoes and season to taste with salt and pepper. Reduce heat to a simmer and cover. Cook for 45 minutes. When soup is cool enough to handle, transfer to a food processor and process until smooth. Pour soup through a strainer. Return soup to pan and add cooked rice and chicken. Bring to a boil and reduce heat to a simmer for 5 minutes. Adjust seasonings and sprinkle with cilantro to serve.