Heat waffle maker; spray with cooking spray. Remove cinnamon rolls from can; set icing aside.
For each waffle, place 1 cinnamon roll in center of waffle maker; close. Bake 3 to 4 minutes or until waffle is thoroughly cooked and golden brown.
Meanwhile, in small bowl, stir together reserved icing, powdered sugar, milk and vanilla until glaze is smooth.
Serve glaze over hot waffles.