Grill the tuna steaks, brushing them first with a little oil, for about 1-11/2 minutes each side. They should still be pink in the middle. Make the vinaigrette in the usual way. Cut the tuna into large chunks, toss in a little dressing and leave to cool. Slice the potatoes while still hot. If they are very small, leave them whole. Toss in a little more dressing then leave to cool. Boil the green beans for about 4 minutes. Drain, run under the cold tap and then drain again thoroughly and mix in with the potatoes. Place the remaining dressing in a large salad bowl. Just before serving, make the salad, starting with the lettuce and adding all the other ingredients, mixing lightly with your fingers as you go. DISCLAIMER(c) Copyright 1996 - SelecTV Cable Limited. All rights reserved. Carlton Food Network http://www.cfn.co.uk/