In small bowl, whisk together yogurt, boullion, garlic, and pepper. Blend. Place in a shallow glass dish. Add the chicken breasts, turnign to coat all sides with marinade. Cover and refrigerate at least 2 hours. Remove chicken from dish and discard leftover marinade. Grill or broil chicken until cooked through, approsimately 5-6 minutes per side.

This is great served with wild rice and a green salad. I usually take the chicken skins off before marinating.