Bring a large pot of lightly salted water to a rolling boil. Cook the penne in the boiling water, stirring occasionally until tender yet firm to the bite, about 11 minutes; drain.
Return the drained pasta to the pot; stir the butter, Parmesan cheese and Gorgonzola cheese into the pasta and place over medium heat; cook until the cheese is completely melted. Pour the cream into the pasta mixture; stir. Remove from heat and fold the pear into the pasta mixture. Top with walnuts. Season with pepper to serve.