Preheat oven to 425 degrees F. Lightly grease a 15x10-inch cookie sheet or 15x10x1-inch baking pan. Unroll pizza dough. Transfer to greased pan, pressing out dough with your hands to a 12x10-inch rectangle. Build up edges slightly. Bake for 7 minutes. Remove from oven.
Meanwhile, in a small bowl combine olive oil and garlic. Brush over hot crust. Sprinkle with half of the cheese blend. Arrange sliced potatoes over all. Sprinkle remaining cheese and the rosemary over potatoes. Bake for 12 to 15 minutes or until crust is golden brown. Makes 10 appetizer servings.