In a skillet, cook and crumble sausage over medium heat until no longer pink and lightly browned; drain. In a large bowl, combine sausage, cheese, baking mix, onion, mushrooms and milk; mix well. Shape mixture into 36 walnut-size balls and place on a greased, shallow baking dish. Bake at 350°F for 15 - 20 minutes or until lightly browned. Remove from oven and let rest for 5 minutes before serving.
Serve with barbeque or chutney sauce.