Preheat oven to 400 degrees F.

Wash and cut the potatoes into quarter wedges. Juice lemons and with a sharp knife peel away the white pith. Cut rind into 1/4-inch strips.

Combine the lemon rind, half the juice, roasted garlic, rosemary, and oil in a roasting pan. Add the potatoes, mix well, and marinate overnight.

Preheat a grill.

Drain the potatoes in a colander reserving the lemon and garlic. Grill the potatoes on the 2 cut sides, just to mark slightly.

Using the same roasting pan, place the potatoes, lemon rinds, and garlic back in the pan and roast for 12 to 15 minutes, shaking and tossing the pan every 5 minutes.

Season with salt and pepper, and drizzle remaining lemon juice if desired.