1 TbspMayonnaise½ cupTuna in spring water (Main)1 tspDijon mustard1 tspTarragon, finely chopped2 tspFlat leaf (Italian) parsley, finely chopped1 to tasteSalt & freshly ground pepper3 tspSpring onions, finely chopped2Ciabatta bread, rolls1 to serveButter1 to serveTomato, sliced1 to serveSpinach leaves1 to serveCheddar cheese, sliced