Combine chicken and mojo in a large zip-top plastic bag; seal and marinate in refrigerator 2 hours, turning occasionally.
Combine onion and parsley in a small bowl.
Remove chicken from bag; pat dry. Heat oil in a large nonstick skillet over medium-high heat. Add chicken; cook 4 minutes on each side or until done. Drizzle each breast with 1 teaspoon lime juice; top each serving with 2 tablespoons onion mixture. Serve with lime wedges, if desired.