Line a baking sheet with aluminum foil (optional for quick clean up).
Mix potatoes in a bowl with olive oil, rosemary, salt, and pepper. Toss spaciously onto a baking sheet.
Roast (uncovered) ~10 minutes, move potatoes around and redistribute evenly, and bake for ~ 12 - 15 minutes or until crispy on the outside and tender on the inside.
Add salt to taste. Top with fresh chopped parsley and add sour cream if you like. Happy Eating! Beckie
Notes
Use two baking sheets if potatoes are too close together. You want them to roast and not steam, which is what they will do if they are placed to close together.