Start to finish: 1 hour and 30 minutes
4 teaspoons vegetable oil
4 teaspoons minced fresh rosemary
2 teaspoons minced fresh thyme
2 garlic cloves, minced
2 (1 1/2- to 1 3/4-pound) racks of lamb, fat trimmed to 1/8 to 1/4 inch and rib bones frenched
Salt and pepper
1 (13 by 9-inch) disposable aluminum roasting pan (if using charcoal)
Combine 1 tablespoon oil, rosemary, thyme, and garlic in bowl; set aside. Pat lamb dry with paper towels, rub with remaining 1 teaspoon oil, and season with salt and pepper.
— For a charcoal grill: Open bottom vent completely and place disposable pan in center of grill. Light large chimney starter filled with charcoal briquettes (6 quarts). When top coals are partially covered with ash, pour into 2 even piles on either side of disposable pan. Set cooking grate in place, cover, and open lid vent completely. Heat grill until hot, about 5 minutes.
— For a gas grill: Turn all burners to high, cover, and heat grill until hot, about 15 minutes. Leave primary burner on high and turn off other burner(s).
Clean and oil cooking grate. Place lamb, bone side up, on cooler part of grill with meaty side of racks very close to, but not quite over, heat source. Cover and cook until meat is lightly browned, faint grill marks appear, and fat has begun to render, 8 to 10 minutes.
Flip racks bone side down and slide to hotter part of grill. Cook until well browned, 3 to 4 minutes. Brush racks with herb mixture, flip bone side up, and cook until well browned, 3 to 4 minutes. Stand racks up, leaning them against each other for support, and cook until bottom is well browned and meat registers 125 degrees (for medium-rare), 3 to 8 minutes.
Transfer lamb to carving board and let rest for 20 minutes. Cut between ribs into separate chops and serve.
Nutrition information per serving: 387 calories; 189 calories from fat; 21 g fat (8 g saturated; 0 g trans fats); 150 mg cholesterol; 572 mg sodium; 1 g carbohydrate; 0 g fiber; 0 g sugar; 46 g protein