Grill or broil sausage for 12 minutes, flipping over halfway through cook time. Let cool slightly, then slice into 1/2-inch pieces.
Prepare tortellini according to package directions. Drain tortellini and return to pot. Drizzle olive oil over tortellini and stir to coat.
Pour sauce and any optional ingredients into a medium saucepan and cook over medium heat until heated through, about 5 minutes.
Spoon tortellini into bowls and top with a generous portion of sauce.
Serve immediately. Top with parmesan, crushed red pepper and basil if desired.