Tuna is lovely and not dry at all, so long as you don't over cook it - which is very very easy. It takes very luittle cooking, a minute either side. It should be pink inside still. I don't like it still jelly like inside but you do have to be careful not to take it too far, else it will be dry - and dry fresh tuna isn't pleasant.
It tastes very different to tinned tuna, and IMo is much nicer.
I tend to serve it with salad, and then either rice, cous cous, new potatoes or jackets.
Tuna tastes lovely and IMO the worst thing you can do is smother it in a sauce, as you lose the flavour. Just a squeeze of lmon or lime, a bit of seasoning, a quick pan fry eother side and it is done.
I wouldn't recommend a white wine sauce with tuna. With a white fist yes, or salmon, but not tuna.
My DH also encrusts tuna with toasted sesame seeds. It is yummy.
The soy/butter simple sauce just adds a bit more of an Oriental flavour to go with the sesame seeds. We had this in a high class restaurant whilst on holiday and tried to copy it at home - with great results!!
oooh yummy I was going to suggest the same as Stirling....just make sure you just gently sear the Tuna and don't over cook it so its pink in th emiddle, served with a lovely dressing a salad nicoise is a perfect meal every time!