Place oven rack on next to lowest shelf.
Preheat oven to 450°F.
Grease 6 deep muffin or custard cups and sprinkle with Parmesan; set aside.
Combine milk, flour, butter and salt in medium bowl.
Beat in eggs just until blended (overbeating will reduce volume).
Fill cups 3/4 full.
Bake 15 minutes.
Reduce heat to 350°F (do not open oven door) and bake 20 minutes more.
Carefully remove popovers with spatula and serve.