Step 3
Meanwhile, melt butter in large saucepan on medium heat. Add shallots and garlic; cook and stir 2 min. Add flour; cook 2 min. or until hot and bubbly, stirring constantly. Gradually add milk; cook and stir 2 to 4 min. or until thickened. Add mustard and 1/2 cup Parmesan; mix well.