Preheat the oven to 400 degrees F. Line a baking sheet with foil, spray it lightly with cooking spray, and set it aside.
Mince the garlic and rosemary and place them in a gallon zip top bag.
Chop the potatoes and add them to the bag, as well.
Add the olive oil, salt, and pepper to the bag. Zip it closed and toss everything around until the potatoes are well-coated with oil, rosemary, and garlic.
Put the potatoes on the baking sheet in an even layer.
Roast for 40 minutes, or until the potatoes are fork-tender and slightly browned. Use a spatula to toss potatoes around on the baking sheet every 15 minutes or so, to ensure even browning.
Notes
Notes: These potatoes are also lovely when using a mixture of fresh rosemary and fresh thyme. Dried herbs can also be substituted, but you will want to use a smaller amount of dried herbs than fresh.