Cook beef and onion, drain excess fat. Stir in cheese, parsley and milk. Prepare biscuit mix according to package instructions. Divide in half then roll into two 8 inch circles. Press one circle into one well greased (use Pam or the equivalent) 8 inch round glass baking dish. Spread meat mixture over biscuit. Place other circle over top, press edges to seal.
Bake in a 375 degree oven for 20 to 24 minutes. Cut into wedges and serve with vegetable sauce – heat celery soup with 1/3 cup milk – serve hot.