Lemon-Rosemary Chicken Halves

***PASTE***
1/4 cup packed fresh rosemary sprigs
1/3 cup olive oil
1 lemon, zest and juice of
1-1/2 tablespoon chopped onion
2 garlic cloves
1-1/2 teaspoons coarse salt

2 whole chickens -- halved
OR 6-pounds chicken
1 lemon -- cut in wedges
fresh rosemary sprigs
lemon slices

At least 3 hours and up to the night before you plan to grill chicken, prepare paste. Puree rosemary with oil in blender, preferably, or a food processor. Let rosemary steep in the oil for 5 to 10 minutes. Strain mixture to remove tough little leaves. Return oil to blender, add remaining ingredients, and puree. The paste will be somewhat soupy. Coat each chicken half thoroughly with paste, rubbing inside and out and working as far as possible under the skin without tearing the skin. Place chicken in a plastic bag and refrigerate. Fire up grill, bringing the temperature to medium (4 to 5 seconds with the hand test). Remove chicken from refrigerator and let sit covered at room temperature for about 30 minutes. Drain chicken and blot any excess moisture from surface. Transfer chicken halves to grill and arrange them skin-side up. Grill uncovered over medium heat for about 20 minutes, without turning, then cook an additional 30 to 40 minutes, turning every 5 to 10 minutes, ending with chicken skin side down for a final crisping. You want chicken skin to face the grill enough to render its fat and brown, but not burn. Watch for flare-ups, shifting halves away from flame if necessary. Squeeze lemon wedges over chicken's cavity about halfway through cooking. If grilling covered, cook chicken starting skin-side up over medium heat for about 15 minutes, without turning, then cook an additional 25 to 30 minutes, turning three times and squeezing lemon wedges over chicken's cavity about halfway through cooking. Arrange chicken on a platter. Garnish with rosemary and lemon slices, if you wish, and serve immediately. Serves 4.