In a mixing bowl, whip together mayonnaise, sour cream, lime zest, and juice, dill, Dijon mustard, minced garlic, and a pinch of salt and pepper.

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

Remove shrimp and place them in an ice water bath for 3 minutes to cool completely.

Slice the cucumber into small cubes and chop the green onions.

Combine the chilled shrimp, cucumber, and green onions in a large bowl. Drizzle with dressing and mix well.

Serve immediately or refrigerate for later use, ideally within a couple of days.