In a large bowl, combine the shrimp and eggs and refrigerate.
In a medium bowl add onion, dill, garlic, lemon zest and juice, horseradish, mayonnaise and sour cream. Mix until thoroughly combined, adding salt and pepper to taste.Add the dressing to shrimp and egg and gently combine. Adjust seasonings if needed.
Portion shrimp salad onto toasted bread. Arrange on a platter, garnish with dill and serve.
This easy appetizer recipe is great for large gatherings and can be easily halved for fewer guests. Serve with a glass of sparkling wine or beer.