Pour milk and maple syrup into a medium-sized saucepan and turn heat to medium. Let it warm until steaming, but not boiling. In a bowl, toss together cheese, cornstarch and rosemary. Add this to warm milk and turn heat up slightly, constantly stirring to melt cheese evenly. Cook for about 5 minutes, until cheese is melted and smooth. Stir in salt and garlic powder, then add sausage. Mix well and serve immediately.