1. Prick the chicken breasts all over with a fork several times so the marinade can penetrate the breast meat. Arrange the chicken breasts in a single layer in a shallow glass or ceramic dish. In a bowl, combine 1/3 cup of the lemon juice, salt, and saffron. With your hands, rub this mixture into the chicken breasts.
2. In a small skillet over medium heat, toast the coriander seeds, red pepper flakes, and cumin for about 2 minutes, stirring constantly. Place in a food processor; add the garlic, ginger, and 4 tbsp of the yogurt, and blend for 30 seconds. Add the remaining yogurt, mix well, and pour over the chicken breasts. Cover tightly and marinate at room temperature for at least 12 hours (or 24 hours in the refrigerator), turning the breasts several times.
3. Prepare the grill or heat the broiler. In a small saucepan over medium heat, melt the butter. Remove the chicken from the marinade and drain off the excess. Baste the chicken breasts with the butter and grill 7 to 9 inches from the hot coals for 4 to 5 minutes on each side, starting with the gone side toward the heat.
4. When the chicken breasts are done, sprinkle with the remaining 2 tablespoons of the lemon juice.
From Chicken Breasts by Diane Rozas.