Step 2
Preheat the oven to 350℉. Mash the potatoes with a potato masher or ricer until they reach the desired consistency. Add ½ cup of the cheese, the Greek yogurt, ½ cup of the milk, the butter, rosemary, 1 tablespoon of the salt, and pepper, and stir until combined. You may use the masher to combine the ingredients, but just make sure you don't over-mash or the potatoes may become gluey. Add as much of the remaining milk as desired and adjust the seasoning, if necessary.