Step 1Boil potatoes in 2-quart saucepan of salted water until fork tender, about 20 minutes. Drain well and cut in halves (or quarters for larger potatoes). Transfer to large bowl.
Step 2Season potatoes with salt to taste and generous grinding of pepper. Drizzle olive oil over potatoes. Add egg white and mix to coat potatoes. Sprinkle with rosemary and cheese and mix gently.
Step 3Place potatoes on lightly greased baking sheet and bake at 350 degrees until potatoes turn golden brown, 15 to 20 minutes. Serve immediately.