- a 7- to-8 pound leg of lamb, trimmed of excess fat, boned, and butterflied by butcher (4 to 4 3/4 pounds boneless)
- 2 onions, chopped
- 6 large garlic cloves, chopped
- 3/4 cup red wine vinegar
- 1/2 cup honey
- 1/3 cup Worcestershire sauce
- Accompaniment: hot red pepper relish
- 2 pounds red bell peppers, chopped fine (about 4 cups)
- 2 onions, chopped (about 2 cups)
- 2 cups cider vinegar
- 3/4 cup sugar
- 2 teaspoons mustard seeds
- 2 teaspoons salt
- 1 teaspoon crushed dried hot red pepper flakes
- Cut lamb into 2 pieces where there is a natural separation in meat and put each piece into a large sealable plastic bag.
- In a food processor, purée all remaining ingredients (except relish) until smooth and divide marinade evenly between plastic bags. Seal bags, pressing out excess air, and put in a shallow baking pan. Marinate lamb, chilled, turning bags once or twice, at least 8 hours or overnight.
- Prepare grill.
- Discard marinade and grill lamb in batches if necessary on an oiled rack set 5 to 6 inches over glowing coals 7 to 10 minutes on each side for medium-rare. Transfer lamb to a cutting board and let stand 10 minutes.
- Serve lamb, thinly sliced across the grain, with relish.
- In a heavy saucepan, stir together ingredients and simmer, stirring occasionally, about 1 hour, or until reduced to about 3 cups. Relish may be made 1 month ahead and chilled, covered.
- Serve relish chilled or at room temperature.