Tokaji: It sounds Japanese, comes from Hungary and tastes like nothing else

Ignorance may be bliss, but enlightenment is even more blissful. That's the position I found myself in after an hour in a basement room of the offices of the Royal Tokaji Company. My hour brought me fully up to speed on the subtleties of Tokaji. Or Tokaj, as it is sometimes spelled. Or Tokaji Aszu, as it should be called. Hungary's only world-class wine, this sweet wine is unique in the way it's made (you can't say that about many wines), unique in the tricks that history has played with it and unique in what it delivers to the jaded palate. I left this tasting with the most wonderful flavours lingering in a very happy oral cavity.

Tokaji Aszu comes from vineyards in area of hilly land in north-east Hungary, where it's been made since the 16th century by a very strange method that hasn't changed a great deal. The grape varieties are Furmint and Harslevelu, and the best berries are picked in a state of advanced shrivelling from noble rot, Botrytis cinerea; aszu means "dried berries". They're placed in tubs, called puttonyos, each holding 25kg to 30kg of grapes, and trodden or crushed. That dense, sweet pulp is added to lighter base wine (which may contain Muscat) in 130-litre vats, with the number of puttonyos determining the sweetness of the final product: five puttonyos is the entry level for real character.

Communism nearly killed Tokaji. There was no investment in the vineyards and attention to quality lapsed. In 1989, however, foreign investors rushed to take advantage of the dormant potential. The wine writer Hugh Johnson and winemaker Peter Vinding-Diers were the first with their purchase of my recent hosts, Royal Tokaji. French insurance companies (which own a number of fine estates in several countries) followed. Vega Sicilia, makers of Spain's most expensive wine, also followed. The first vintage of "reborn" Tokaji was in 1990.

These wines are like no others, in sensory impact as well as production. They are deep gold in colour, almost like a light single-malt, and their high sugar content is balanced – almost masked – by startlingly high acidity. They don't necessarily strike you as sweet wines at all. The flavours are of dried fruit, golden sultanas or apricots, with citrussy notes that can range from grapefruit to mellow orange-peel, and there are often flowery aromas as well. Best of all, the vineyards produce dramatically different results, as you would expect in any area where terroir really means something. Just take two of my favourites: Nyulaszo 1995 (six puttonyos) is lean and tending towards an almost mineral crispness, while Szt Tamas (same year and same puttonyos) is lush and generous.

Uppermost quality in sweet wine never comes cheap, but these treasures come with price-tags that will make you gulp. The entry-level Royal Tokaji Blue Label 1996 Aszu is most widely available and cheapest, at around £15 to £18. My two favourites, Nyulaszo and Szt Tamas, weigh in at £36.30 and £58.95. And remember, these are 50cl bottles, the standard size.

But if the prices make you gulp, a sip will make you swoon, sigh and smile. And the wines would make a perfect present for someone too young to drink them now, because the acid and sugar mean they last almost indefinitely. So think about it, when you feel like a self-indulgent treat that is truly unique in the wine-drinker's range of possibilities. Berry Bros & Rudd (0870 900 4300) sells all the Royal Tokaji wines, and you can ring the company (020 7495 3010) for other stockists. Also look for wines from the other company whose wines I have tasted, Disznoko and Oremus. Ignorance was OK. It wasn't a patch on enlightenment.