Stuffed Mushroom Dip

"Both times I ate this, I ate about 1/3 of the baking dish!"

107 Calories

23g Carbohydrates

16g Protein

239mg Potassium

9g Fiber

14g Sugar

cooking spray
1 tablespoon salted butter
1/4 cup Italian-seasoned breadcrumbs
8 ounces hot Italian pork sausage
2 (8-ounce) packages sliced fresh cremini mushrooms, chopped (about 5 cups)
1 tablespoon finely chopped garlic (from 3 medium garlic cloves)
1/2 teaspoon freshly ground black pepper
1/2 teaspoon kosher salt
1 cup sour cream
1 (7-ounces) container chive-and-onion cream cheese, at room temperature
1/4 cup chopped fresh flat-leaf parsley, plus more for garnish
3 ounces low-moisture part-skim mozzarella cheese, shredded (about 3/4 cup), divided
1/2 cup freshly grated Parmesan cheese, divided
crostini for serving