Preheat oven to 350° F.
Place mashed potatoes to a thickness of about 1/2 inch on top of pizza crust.
Bake until potatoes are warm (about 160°s; F).
Top with a heavy layer of shredded Cheddar cheese and sprinkle bacon bits on the top of cheese. Place back into oven and heat until cheese is melted.
Serve with sour cream and chives.
Makes: 4