Grilled Chicken with Garlic and Walnut Sauce

• 2 chickens (2½ pounds each), quartered, well rinsed, and patted dry
• Salt and freshly ground black pepper, to taste
• ½ cup olive oil
• ¾ cup fresh lemon juice
• 3 cloves garlic, minced
• 8 sprigs fresh tarragon, stems crushed with the back of a knife
• 1½ cups walnut pieces
• 5 cloves garlic, peeled
• ½ cup chopped fresh cilantro
• 1 cup chicken stock or canned broth, warm (not hot)
• 3 to 4 tablespoons fresh lemon juice
• Salt, to taste
• ¼ teaspoon ground coriander
• ¼ teaspoon ground fenugreek
• ¼ teaspoon cayenne pepper
• ½ teaspoon ground turmeric

1. Rub the chicken pieces thoroughly with salt and pepper. Combine the olive oil, lemon juice, garlic, tarragon, and additional salt and pepper in a shallow dish. Add the chicken and turn to coat with the marinade. Cover and refrigerate for at least 6 hours, turning occasionally.

2. In a food processor, combine the walnuts, garlic, and ¼ cup of the cilantro. Process until the walnuts are finely ground. Transfer to a bowl and stir in the stock, lemon juice to taste, salt, coriander, fenugreek, cayenne, turmeric, and the remaining cilantro. Let the sauce stand at room temperature, covered, for at least 2 hours before serving. Makes about 2 cups.

3. Prepare the coals for grilling until coated with white ash, or preheat the broiler. Oil the grill or broiler rack.

4. Remove the chicken from the marinade and, without drying, grill or broil it 3 to 4 inches from the heat, turning a few times and basting with the marinade. The chicken is ready when the juices run clear when the thickest part of the thing is pricked with a skewer, after about 30 minutes.

5. Serve the chicken with the sauce in a sauceboat.