- Preheat oven to 400 degrees. 
- Mist a 9x13 baking dish with cooking spray. 
- Arrange mushrooms, cavity side up, in dish. 
- Chop mushroom stems finely. 
- Melt butter in a medium skillet over medium-high heat. 
- Add onion, chopped mushroom stems and turkey sausage crumbles. 
- Sprinkle with salt and cook, stirring often, about 5 minutes. 
- Transfer turkey sausage mixture to a bowl. 
- Let cool for 10 minutes, stirring occasionally. 
- Stir in bread crumbs and parsley. 
- Fold in goat cheese. 
- Season with salt and pepper. 
- Sprinkle mushroom caps with salt and pepper. 
- Spoon filling mixture into mushrooms, piling in center. 
- Bake until lightly browned on top, about 15 minutes. 
- Let cool slightly before serving.