Serves 4 INGREDIENTS 2 heads celery root 2 tablespoons Veuve Cliquot yellow label champagne Zest of 1 Meyer lemon, juice of half Best quality extra virgin olive oil Kosher salt Freshly ground white pepper 1 dozen very fresh welfleet oysters (call pat woodbury) Leaves from 1 head celery ½ cup fresh chervil leaves ¼ cup…