Stir together cream cheese and 1/4 cup Green Goddess Dressing in a small bowl. Spread cream cheese mixture over tortillas. Top with spinach, smoked salmon, cucumber, and onion. Drizzle with remaining 1/4 cup dressing. Tightly roll up tortillas, tucking in ends (use a toothpick to secure, if needed). Serve immediately (or wrap in plastic wrap and chill up to 24 hours).