Cut each potato lengthwise into 8 wedges, about ¾ inch thick.
Toss potatoes with oil, salt, granulated garlic, and pepper in a large microwave-safe bowl.
Microwave, covered, until potatoes are nearly tender, 9 to 12 minutes, stirring every 3 minutes. Uncover and set aside while heating the grill.
Grill on high with potatoes cut side down until well browned on all sides, 3-4 minutes per side. Season with salt & pepper.
