There's a lot of good places in W A Khan - the Red Pepper near the air museum does a good steak and the food at l'Atmosphere is excellent and there's a swimming pool where you can enjoy the bikini-clad aid workers, post prandially.
The Gandamack does a reasonable lunch, including "Grilled Sliced Aborigine", which turned out to be an Aubergine dish.
Avoid the Chinese restaurant near the Emergency hospital. It gets raided all the time because they offer a rather more intimate 'Chinese takeaway' which involves women rather than spring rolls and thus upsets the Pastuns.
Depends where you go in Kabul - personally the best I've found is the KBR place in Camp Souter. IJC is okay, and the so called 'Supreme Catering' in the HQ are anything but! To be fair its a challenge to cook interesting meals for multiple nationalities day in day out, but what is served up is repetitive and bland. Best food I've had to date in ISAF was at FOB Fenty, over in RC(E) - superb food out that way.
Please don't take this as a whine though - if the worst that things get out here is 'repetitive and bland' then frankly I'm all to well aware that I (and anyone else up here) is on a total luxury cruise compared to the real world - shame that many of our allies staff don't think that and just whine incessantly. Also don't get me started on the sodding 'official rules for use of camp Sauna by registered couples'.
You know what might be good...you open a pizza restaurant in Kabul etc. with mopeds for delivery, make sure your delivery boys are pro-al Queda and order a pizza per night at each FOB. Either you follow him to see which routes are clear or you watch him show you which ones are not.
In general if you are in a Supreme cookhouse, its going to be shit, if you are in a KBR cookhouse its going to be good. I am told that you can order a cracking curry from down town and have it delivered.