In a medium bowl, combine mayonnaise, lemon juice and zest, dill, mustard, and minced garlic. Whisk until smooth and creamy.

Bring a large pot of water to a boil. Add shrimp and cook for 2 to 3 minutes until pink and opaque. Drain.

Prepare an ice bath with cold water and ice. Transfer cooked shrimp to the ice bath for 3 minutes to cool.

Drain shrimp and pat dry. In a mixing bowl, combine shrimp with chopped red onion and diced celery. Pour dressing over and mix gently.

Serve in butter lettuce leaves or in a bowl. Garnish with additional dill or lemon wedges as desired.