Preheat oven to 375F.

Thinly slice the cucumber into rounds after peeling.

Chop the fresh dill.

Juice the lemon.

Grate the lemon peel.

Melt the butter.

In a medium bowl, combine cucumber, 1 1/2 teaspoons dill, and 1 1/2 teaspoons lemon juice.

Season the cucumber mixture with salt and pepper.

Toss the cucumber mixture to coat.

In a small bowl, combine sour cream, lemon peel, and the remaining 1 teaspoon lemon juice.

Season the sour cream mixture with salt and pepper.

Stir the sour cream mixture to blend.

Brush a baking sheet with some of the melted butter.

Arrange the trout fillets, skin side down, on the prepared baking sheet.

Brush the trout fillets with the remaining melted butter.

Sprinkle the trout fillets with salt and pepper.

Bake until the trout is just opaque in the center, approximately 10 minutes.

Divide the cucumbers among 2 plates.

Using a spatula, carefully place the baked trout fillets atop the cucumber on each plate.

Spoon the sour cream sauce over the trout fillets on each plate.

Sprinkle the trout with the remaining 1 1/2 teaspoons dill on each plate.

Serve immediately.