Step 1In a large bowl, whisk together the cider vinegar, honey, olive oil, mustard and salt and pepper to taste. Set aside.
Step 2On a large cutting board, mince together the chives, dill, mint and edible flowers until they resemble fine confetti. Reserve one-eighth cup of the mixture and stir together the rest in a medium bowl with the creme fraiche and lemon zest. Set aside.
Step 3Toast the pumpernickel bread in a toaster until slightly crisp, cut in half diagonally and spread with the herbed creme fraiche.
Step 4Arrange four slices of smoked salmon in a single layer on each of four large plates. From the bowl of dressing, reserve two tablespoons and set aside. Add the mesclun to the bowl of dressing and toss to combine. Pile one-fourth of the salad on top of the salmon on each plate, being sure to get a little height to the salad. Stand two toasts against the salad. Sprinkle the reserved herb confetti and drizzle the reserved dressing around the salmon. Serve immediately.