Combine the consommé or stock, cinnamon, star anise, ginger, lemongrass and chicken in a large saucepan. Bring to a simmer over medium heat. Reduce heat to low, cook for 15-20 minutes or until chicken is cooked through. Transfer the chicken to a board, set aside for 5 minutes then shred.
Meanwhile, heat a large non-stick frying pan over high heat. Spray the mushrooms lightly with oil and cook in the hot pan in two batches, for 4-5 minutes until just tender.
Strain the stock mixture, discard the solids and return stock to the pan. Bring to boil. Add the mushrooms, lime juice and fish sauce.
Divide the chicken between serving bowls. Ladle over the stock, top with green onions, chilli, bean sprouts and mint. Serve.