Toss half a 28-ounce bag frozen steak-cut fries with 2 teaspoons olive oil and 1 teaspoon each coarsely ground pepper and chopped rosemary. Spread on a baking sheet and bake at 425˚ until crisp, 30 minutes. Grate 4 ounces havarti on the large holes of a box grater. Divide the cheese into eight 3-inch rounds on a parchment-lined baking sheet; season with pepper and chopped rosemary. Top with the fries. Bake until the cheese is browned around the edges, 12 to 15 minutes. Remove with a thin spatula.