Preheat oven to 400˚F.
In small bowl, combine American Grana®, garlic powder, paprika, oregano, salt, and pepper. Stir with a fork until mixed.
Drizzle olive oil into 9×13 glass baking dish. Use a brush to evenly coat the dish.
Slowly sprinkle cheese mixture over bottom of pan, so it is evenly spread over the entire surface.
Arrange potatoes in a single layer, cut side down, on top of cheese mixture. Press down to insure potatoes are flat and in contact with cheese layer. Top with 1 Tbsp. of American Grana®.
Bake for 30-40 minutes, or until cheese is browned and potatoes are soft when pressed or pierced with fork. Remove from oven and rest for 5 minutes. Carefully remove potatoes from pan with a spatula, be sure to keep the cheese layer intact on the cut side of potato. (Use a paring knife to cut cheese between the potatoes, if necessary.)
Arrange on serving platter cheese side up. Serve with Mascarpone mixed with chopped scallions or chives.