Preheat oven to 425.
On a cutting board, cut the potatoes into 1" cubes. Place in a glass baking dish.
Drizzle potato cubes with olive oil. Top with parmesan, garlic and black pepper. Toss in the baking dish (this saves yourself from washing an extra bowl!)
Bake for 35-45 minutes until potatoes are crispy and brown around the edges. They should be tender in the center when pierced with a fork.
Remove from oven and add to serving plate. Top with cheddar, chives or green onions, and a spoonful of sour cream. I like to salt and pepper before serving!