Preheat oven to 400. Cut potatoes in halves or quarters, leaving skins on. Place in bowl with olive oil, salt, pepper & garlic; toss until potatoes are well-coated. Prepare larger baking sheet: either spray with cooking spray, or wipe down with olive or canola oil. Spread potatoes out in one layer on sheet. Roast at least an hour until brown and crisp, turning twice during cooking for even browning.