Pakistan of the 80's for me. Perhaps India under Ganguly falls close by because that was some team. Ganguly is rated highly by all cricket fans and experts alike and for good reason! That team was scary, Sehwag, Tendulkar, VVS, Ganguly, Dravid, ZK and Bhajji - one of the strongest XI's to have played the game.
However, owing to the mediocrity of its bowling, I don't think it can be rated as the best ever Asian Test side. That goes to Pakistan of the 80's who posed an ATG attack of Imran Khan, Wasim Akram, Qadir.