1. Preheat oven to 350 degrees.
2. Boil a large pot of water over medium heat.
3. Meanwhile (peel if you want and) cut potatoes into eighths.
4. When water is boiling add potato pieces and boil for 15-20 minutes, or until soft.
5. Drain potatoes and add them to a large bowl.
6. Add butter, yogurt and milk and mix until smooth.
7. Stir in chives, salt and pepper, and 1/2 cup of mozzarella.
8. Spray a 8×8 or bread loaf pan with non stick spray.
9. Add potatoes to pan.
10. Top with bacon bits and slightly push in to the potato mixture.
11. Cover with foil and bake for 30 minutes.
12. Uncover and top with additional mozzarella cheese.
13. Bake for an additional 10 minutes.