Put onion, tenderstem broccoli, mushrooms, chicken, salt, and garlic in an oven dish
Mix together Greek yoghurt, low fat cottage cheese, Dijon mustard, chicken stock, salt, and garlic powder to make the sauce
Pour sauce over the chicken and vegetables
Wrap the dish tightly and bake in the oven at 170°C (fan) for 40 minutes
Remove from oven, uncover, and bake at 180°C for 20 minutes
Serve over cauliflower rice or with a jacket potato/rice
