Preheat your oven to 400°F (200°C).
Rinse and dry the baby potatoes thoroughly with a towel.
In a bowl, toss potatoes with olive oil, garlic, rosemary, salt, and pepper until evenly coated.
Spread potatoes on a rimmed baking sheet in a single layer.
Roast on the bottom oven rack, shaking the pan every 5 minutes.
Bake for about 20 minutes, or until crispy outside and fork-tender inside.
Remove from oven and serve hot.
