Cook 2 minutes, stirring constantly. Remove from heat, and add shredded Provolone a handful at a time, stirring until it melts. Stir in Parmesan cheese and season with salt and pepper, then set aside and let cool to warm room temperature.

Preheat oven to 350 F. In a medium bowl, whisk together Béchamel and spaghetti sauce. In large bowl, combine tortellini and 3/4 of sauce mixture. Pour into a 9x13 casserole dish and spread into an even layer. Drizzle remaining sauce over top. Sprinkle Mozzarella and Parmesan cheeses evenly over top.

Cover with foil and bake 45 minutes. Remove foil, increase temperature to 400F and bake an additional 10 minutes, until cheese is browned and bubbling on top. Allow to sit for 10 minutes before serving.