where can i buy the tea served in korean restaurants?
Are you looking for barley tea? or persimmon tea? I don't know where to buy either downtown but you can get barley tea (ie, roasted barley) at any Korean grocery. Obviously in Koreatown, but I don't know if there are other Korean grocery stores in Manhattan or where they might be. You can make persimmon tea with dried persimmons, ginger, cinnamon, sugar and pine nuts.