1. Place a fine-mesh strainer with a double layer of paper towels over a bowl. Grate the cucumber into a colander and allow the cucumber to drain for about 30 minutes. Once drained, remove any additional liquid from the cucumber and place it in a separate bowl. Add lemon zest and sour cream and stir to combine. Cover with plastic wrap and refrigerate until ready to use.

2. Remove any bones from salmon; remove and discard skin. Chop salmon into small pieces and place in a large bowl (use the back of a knife to smash some of the salmon into more of a paste). Add scallion, parsley, and lemon zest and mix until just combined. Add egg and 1/2 cup breadcrumbs and season with pepper. Mix again until the mixture holds together (add more breadcrumbs if needed). Form into small cakes. Cover with plastic wrap and refrigerate for at least 1 hour. Preheat oven to 400°F.

3. In an oven-safe sauté pan, heat oil over medium-high heat. Add salmon cakes and sear on both sides until lightly golden brown, about 3 minutes per side.

4. Transfer cakes to a paper towel-lined plate and allow to cool.

5. Place cakes on a large serving platter and top each with a bit of cucumber sauce, and a small dollop of Smoked Trout Roe on top.