Spray a pan with low-calorie cooking spray and cook the chicken until almost brown. Remove from the pan and set aside.
Add the onion, carrot, celery and mushrooms to the pan and cook until soft.
Add the tomatoes and lemon juice. Add the chicken back to the pan and sprinkle in the contents of this sachet. Add 500ml water. Mix well. We suggest cooking in the oven, covered for 30-35 mins at 180°C.
Add in the orzo, stir, and return to the oven for 20 mins (uncovered) until cooked thoroughly.
When the orzo is tender, sprinkle with the parsley, if using. Serve and enjoy!