If possible, use fresh sage and freshly grated Parmesan to heighten the flavor of this dish. Makes a huge difference!
Cook cheese tortellini according to package instructions; drain. (You can start on the sauce while the tortellini is cooking).
Heat butter over medium heat in a large skillet. Add sage and slowly cook butter until it begins to brown. (It's okay if the sage darkens and gets crunchy).
Remove from heat; add the hot tortellini. Stir to coat; add parmesan cheese, salt and pepper and toss. (If you choose to add sun-dried tomatoes, add them in with the cheese, salt, and pepper before tossing.).