Step 1Cut the ends off the cucumbers and discard. Cut the cucumbers into 2- to 3-inch chunks; save a 1-inch-long piece and slice it into 12 thin slices. Reserve the slices for the garnish.
Step 2In a food processor, combine the cucumbers, mint, dill, chives and grapes until smooth. Add the chicken broth and process until smooth, then add the creme fraiche. Season with the salt and pepper. Chill or transport in a chilled container. Serve in cups or bowls. Garnish each portion with 3 thin slices of cucumber and a sprig of mint.