In a resealable plastic bag, combine the soy sauce, 1 tablespoon sesame oil, lemon juice, garlic powder and lemon-pepper; add shrimp. Seal bag and turn to coat; refrigerate for 30 minutes.
Drain and discard marinade. In a skillet, saute shrimp in remaining sesame oil until shrimp turn pink, about 3 minutes. Serve with rice if desired. Sprinkle with sesame seeds.