Toss potatoes with olive oil, salt, pepper, and rosemary then place on roasting tray in the oven for 35 minutes (shake pan 2-3 times during this process for even cooking).
Take out and sprinkle evenly with cheese and return to the oven another 10-15 minutes until cheese is melted.
Incorporate juice and zest of the lemon into the sour cream.
Top potatoes with chives and serve with sour cream dipping sauce.