Bak kut is pork rib and teh is tea, but bak kut teh is not prok ribs cooked in tea! It's cooked in Chinese herbs. It is normally taken with a pot of tea served to wash down the oily part of the ribs, therefore the name.
There are plenty of bak kut teh outlets in Kuching, but they all taste different. One of my favourite outlets is the one at Hiong Mon Low Cafe at BDC because it reminded me of a powerful engine, so there must be umph!