Preheat your oven to 350°F.
In a large, oven-safe skillet, cook the sausage until browned.
Add the mushrooms and sauté until tender.
Next, mix in the cream cheese, garlic salt, and sour cream, stirring until everything is well combined.
Fold in half of the mozzarella cheese and stir until melted.
Sprinkle the remaining mozzarella on top and transfer the skillet to the oven.
Bake for 15 minutes or until the cheese is bubbly.
For a golden, crispy finish, broil for an additional 2-4 minutes.
Serve warm with your favorite crackers or sliced baguette!