Cook the tortellini according to package directions.
While tortellini is cooking, add the butter and heavy cream to a sauce pan over medium heat and cook, stirring often, until the butter has melted.
Add the Parmesan cheese to the butter mixture and whisk constantly over low heat until the cheese has fully melted.
Season the Alfredo sauce with salt and pepper.
Drain the tortellini and add to the Alfredo sauce. Toss to coat.
Sprinkle with fresh basil just before serving.
Notes
Add chopped, cooked chicken to this dish, if desired. It's also good with sliced steak. Fresh or frozen tortellini is preferred, but dried also works just fine. Be sure to use shredded parmesan and now the kind in the green shaker can for the best results.