1. Turn all burners to high, cover, and heat grill until very hot, about 15 minutes. Use grill brush to scrape grill clean; oil cooking grate. Leave primary burner on high and reduce other burners to medium.

2. Meanwhile, heat olive oil, garlic, rosemary, and 1/2 teaspoon salt in small skillet over medium heat until sizzling, about 3 minutes. Reduce heat to medium-low and continue to cook until garlic is light blond, about 3 minutes. Pour mixture through fine-mesh strainer into small bowl; press on solids. Measure 1 tablespoon solids and 1 tablespoon oil into large bowl and set aside. Discard remaining solids but reserve remaining oil.

3. Place skewered potatoes in single layer on large microwave-safe plate and poke each potato several times with skewer. Brush with 1 tablespoon strained oil and season liberally with salt. Microwave on high power until potatoes offer slight resistance when pierced with tip of paring knife, about 8 minutes, turning them halfway through cooking time. Transfer potatoes to baking sheet coated with 1 tablespoon strained oil. Brush with remaining tablespoon strained oil; season with salt and pepper to taste.

4. Place potatoes on hotter part of grill. Cook, with lid down, turning once, until grill marks appear, about 4 minutes. Move potatoes to cooler part of grill; and continue to cook with lid down until paring knife slips in and out of potatoes easily, 5 to 8 minutes longer. Remove potatoes from skewers and transfer to bowl with reserved garlic/oil mixture; add chives and toss until thoroughly coated. Serve immediately.

Serves 4