Bring a large pot of well-salted water to a boil. Cook the pasta according to package directions until al dente. Drain, toss with the olive oil and set aside to cool.
Stir the seasoning mix with the sour cream. When the pasta is cool, toss with the sour cream mixture, chicken, bacon and Parmesan cheese, if using. Chill for at least 1 hour before serving cold.
