Preheat the oven to 375F/190C.
Clean the portobello mushrooms with a dry paper towel to eliminate any excess dirt and remove the stems.
Spread 2 tablespoons of Tomato Sauce per Mushroom cap.
Remove the sausage from the casing and press into the mushroom cap.
Top the stuffed mushrooms with the shredded mozzarella cheese
Bake for 40 minutes.