Melt butter in a medium saucepan over medium heat. Add garlic; cook 1 minute, stirring frequently. Stir in flour. Gradually add milk, stirring with a whisk. Cook 6 minutes or until mixture thickens, stirring constantly. Add 1 cup Parmigiano-Reggiano, cream cheese, and salt, stirring with a whisk until cheeses melt. Toss sauce with hot pasta. Sprinkle with remaining 1/4 cup Parmigiano-Reggiano cheese and chopped parsley. Garnish with black pepper, if desired. Serve immediately.