Sprinkle chicken pieces with lemon juice and let stand 30 minutes. Pat dry. Mix flour, salt and pepper; dredge chicken pieces to coat evenly. In a heavy skillet with a tight lid, heat oil and butter. Cook chicken, sprinkling with any leftover flour mixture, until browned on both sides. Remove from skillet and set aside. Add onion and cook until golden. Add onion and cook until golden. Add curry powder and cook for 2 minutes. Gradually beat in water and cream, cook until thickened. Add chicken stock base and ginger, stir, and return chicken to skillet. Cover and simmer, turning chicken once, for 40 minutes or until chicken in tender. Transfer to heated platter and surround with lime wedges. Serve with rice.