Spread one side of each slice of bread with a thin layer of butter. Arrange a single layer of cucumber slices on 4 of the bread slices. Stir together the mayonnaise, chives, mustard and some salt and pepper in a small bowl. Spread a thin layer of the mayonnaise mixture over the cucumbers. Top with the remaining slices of buttered bread. Cut off the crusts and cut each sandwich into three fingers.
Recipe courtesy of Ree Drummond