1. In a large resalable plastic bag, combine the soy sauce, sesame oil and garlic; add chicken. Seal bag and turn to coat; refrigerate for at least 1 hour.
2. Spread cream cheese onto a large serving platter; top with chicken mixture. Sprinkle with onions, peanuts and spinach. Drizzle with sweet-and-sour sauce. Cover and refrigerate for at least 2 hours. Serve with crackers.