Wash 2-3 firm cucumbers and slice them thinly (about 1/8 inch). Sprinkle lightly with salt and let sit in a colander for 10 minutes. Pat slices dry.

In a bowl, combine 1 cup of mayonnaise or Greek yogurt, 2 tablespoons of freshly chopped dill or chives, 1 tablespoon of lemon juice, and a pinch of salt and pepper. Whisk until smooth.

Fold the prepared cucumber slices into the creamy dressing.

Spread butter or extra dressing on one side of each slice of bread. Place a spoonful of cucumber salad on one slice and top with another slice.

Cut the sandwiches into small squares or triangles and arrange on a platter.

Garnish with fresh dill sprigs or cucumber ribbons if desired and serve.