Flavor upon flavor, texture upon texture lend hors d'oeuvres like this one drama as well as playfulness.
Peel cucumber; slice into 24 1/4-inch-thick rounds. Cut out each round with a 1 1/2-inch square fluted cookie cutter. Cover with a damp paper towel; set aside In the bowl of an electric mixer fitted with the paddle attachment, beat the goat cheese and heavy cream until smooth. Transfer to a pastry bag fitted with a #35 star tip; set aside. Slice orange sections in half lengthwise. Cut salmon into 1 1/4-inch triangles.
Lay cucumber slices on a baking sheet. Top each with a triangle of salmon; pipe a small amount of goat cheese on top. Top with an orange slice, beet cubes, and a fennel or dill sprig. Serve immediately.