Wash potatoes. In a medium saucepan, cook the potatoes and carrots, covered, in a small amount of boiling salted water for 12 to 15 minutes or until tender. Drain and let stand until cool enough to handle. Meanwhile, remove the rosemary leaves from the bottom two-thirds of each sprig, leaving the top leaves intact. Soak rosemary sprigs in a bowl of warm water for 10 minutes; drain.

In a small bowl, stir together pesto, shallots, lemon peel and black pepper. In a medium bowl toss the potatoes and carrots with 1/4 cup of the pesto mixture. Set remaining pesto mixture aside.

Use a wooden (see note) or metal skewer to poke a hole through each potato and carrot. Remove lower leaves of the rosemary skewers. Alternately thread potatoes and carrots onto rosemary sprigs (or use eight 6-inch wooden or metal skewers*), leaving a 1/4-inch space between each piece. Add a lemon wedge to the end of sprigs or skewers.

For a charcoal grill, grill the sprigs or skewers on the rack of an uncovered grill directly over medium coals for 10 to 12 minutes or until potatoes are golden brown, turning once. (For a gas grill, preheat grill. Reduce heat to medium. Place sprigs or skewers on grill rack over heat. Cover; grill as above.)

To serve, remove potatoes and carrots from rosemary sprigs or skewers; squeeze grilled lemon wedges over each serving. Pass reserved pesto mixture. Makes 4 side-dish servings.

If using wooden skewers, soak them in water for at least 30 minutes before grilling.