In a medium bowl, combine mayonnaise, sour cream, lime zest, lime juice, fresh dill, Dijon mustard, minced garlic, kosher salt, and a sprinkle of black pepper. Whisk together until smooth and creamy. Set aside or refrigerate for 10-15 minutes.

Bring a large pot of water to a boil over high heat. Add shrimp and cook for 2-3 minutes until vibrant pink and opaque. Remove from heat.

Prepare an ice water bath using cold water and ice. Transfer cooked shrimp to the ice bath for about 3 minutes to chill, then drain.

In a large mixing bowl, add chopped shrimp, diced cucumber, and sliced green onions. Pour the creamy lime dressing over the ingredients and gently fold together.

Taste the salad and adjust seasoning if necessary. Serve immediately or refrigerate for 10-15 minutes to enhance flavors.