Layer half each of the waffles, Singles and ham in 13x9-inch baking dish sprayed with cooking spray, cutting waffles as necessary to fit dish; repeat layers.
Microwave cream cheese in large microwaveable bowl on HIGH 30 to 40 sec. or until softened; whisk until creamy. Gradually add milk, about 1/4 cup at a time, whisking after each addition until blended. Whisk in eggs. Pour over ingredients in baking dish; cover with foil. Refrigerate overnight.
Heat oven to 350ºF. Bake casserole (covered) 50 min. or until knife inserted in center comes out clean, uncovering for the last 20 min.