Cook and drain macaroni, place in oven proof casserole. Melt Velvetta, sourcream & cream cheese in the butter. Add evaporated milk. Stir until smooth.
Add one third of the mozzarella. Pour over macaroni.
Sprinkle remaining mozzarella over top. Bake at 190ÂșC or 30 minutesor until bubbly. Don't let it get brown on top because the mozzarella won'tbe stringy.