Directions

1. Cut two 1/4-inch-deep slashes into the skin side of each piece of chicken. Puree garlic, 1 1/2 teaspoons salt, and the chives in a food processor until a smooth paste forms. Transfer to a bowl, stir in mustard and oil, and season with pepper. Rub mixture onto chicken, as well as under the skin. Cover, and refrigerate for 2 hours.
2. Preheat grill to medium. Grill chicken, about 6 pieces at a time, turning often to prevent flare-ups, about 10 minutes, adding more pieces as chicken browns. Once chicken is crisp and browned, transfer pieces to an indirect- or low-heat area, and grill, until cooked through, checking frequently and turning as needed, to avoid charring, 10 to 12 minutes. (Pierce with a fork to test for doneness; meat should be firm and juices will run clear.) Drizzle with vinegar while warm.
3. Meanwhile, cook sausage on a clean, lightly oiled section of grill, over medium heat. Grill until golden brown, 6 to 7 minutes. Flip, and continue to grill until cooked through, 6 to 8 minutes more. (If using a gas grill, reduce heat to medium-low to finish cooking chicken, then raise to medium for sausage.)