How to Make It
Preheat oven to 425°F. Cut bagel in half crosswise. Slice each bagel half crosswise into 9 rounds. Arrange bagel rounds in a single layer on a baking sheet. Bake in preheated oven until crisp and toasted, about 4 minutes. Let cool completely, about 5 minutes.
Stir together salmon, cream cheese, mayonnaise, sour cream, dill, and salt in a bowl. Serve alongside toasted bagel toasts and cucumber slices.