In a large bowl, whisk together mayonnaise, lemon zest, garlic powder, and wasabi paste. Fold in salmon, chickpeas, celery and cilantro. Season, to taste, with salt and black pepper.
In a medium bowl, combine rice and mirin. Toss to combine and season, to taste, with salt and black pepper. Place a large lettuce leaf on each plate. Divide rice among lettuce cups. Spoon salmon mixture over rice.