Bring 5 quarts of generously salted water to a boil; add Penne and stir. Cook Penne al dente (about 10 minutes). Drain well.
Heat cream in a medium saucepan until mixture simmers. Add cheese and stir until dissolved. Simmer until mixture thickens, about 5 minutes. Add salt and pepper to taste.
Pour sauce over pasta, or serve on the side.