Preheat the oven to 375 degrees. Spray a 9 x 13 pan with cooking spray and set aside.

In a large saucepan being water to a boil over high heat and cook penne according to the package directions. Drain and pour into prepared pan.

In a medium skillet over medium heat, add the sausage. Saute for 5-7 minutes, stirring to crumble, or until browned. Add the onion to the pan and saute for 3 minutes.

Add the spinach, pepper, and salt and saute for an additional 3 minutes or until spinach just begins to wilt. Remove from stove.

Pour the spinach and sausage mixture into the pan with the pasta and mix well. Pour in the Ragu sauce and mix well. Add the Asiago cheese and mix until combined.

Sprinkle the mozzarella cheese on top.

Put the dish in the oven for 25 minutes until cheese is browned and melted. Remove from the oven and enjoy immediately.