Preheat the oven to 180 °C. Grease an ovenproof dish.
1. Season the chicken with salt, pepper, lemon juice and zest. Put into a steamer and steam until done, about 5-7 minutes. Shred finely.
2. Heat a little oil in a frying pan and fry the mushrooms until just done. Add the spinach and heat until wilted.
3.Whisk together the egg and cottage cheese.
4. Mix the cottage cheese mixture gently with the chicken and vegetables and spoon into the dish. Sprinkle on the grated cheese and bake for 30-40 minutes or until the egg has set and the cheese topping melts.
5. Serve with salad.