For the herb salad, finely pluck all the herbs and wash them as briefly as possible in water. For the marinade, mix the mustard, vinegar and chicken stock in a bowl. While stirring constantly, slowly pour in both oils. If the dressing is too thick, add a little more stock, otherwise the herbs will lose flavor. Season to taste with freshly ground sea salt, pepper and lemon juice, if desired. Toss the herbs through the dressing and arrange on plates. Garnish with the capuchin flowers.