Preheat a baking sheet in the hot oven for at least 5 minutes.
While the baking sheet is heating, toss the potatoes with the olive oil and 3/4 teaspoon salt in a large bowl. Then dump the potatoes out onto a baking sheet, spreading to a single layer. Roast for 30 to 35 minutes, shaking the pan every now and then, until the potatoes are cooked through, brown and crispy. Toss the fries in a big bowl with the parsley and cheese.