Potatoes and rosemary – a marriage made in food heaven, for sure! And although I love making the classic dish in the oven all year long, come summer I turn to the grill. Grilled potatoes, marinated twice for maximum rosemary and garlic flavor! As with most things grilled, marinating potatoes before cooking them works wonderfully. Here, we’ll marinate the potatoes in rosemary and garlic for 30 minutes.