Finely grate fresh Parmesan for smooth sauce—pre-grated doesn't work as well.
Prepare pasta according to package directions.
Meanwhile, cook half-and-half and next 2 ingredients in a large heavy nonaluminum saucepan over medium heat, whisking often, 12 minutes or until reduced by one-third (do not boil). Remove from heat.
Whisk in cheese, next 2 ingredients, and desired amount of pepper until sauce is smooth. Toss sauce with hot cooked pasta. Let stand 5 minutes before serving.
This recipe was awful. I followed it exactly, too. The sauce never thickened at all. It was basically like pouring milk over pasta. I highly do not recommend this recipe....