The Vietnamese. Sorry DD South East Asian restaurants make superior iced coffee. Haven't had it? I probably wouldn't have either, but every time I do a story on a Vietnamese restaurant, the owners always ply one on me. "Before you leave let me make you an iced coffee," they say with an air of pride. And since I never turn down free coffee (rule numeral uno), I always oblige. I think poynter would agree w/ me that journalistic ethics end at free coffee. The secret to this ultra refreshing drink? Each cup is brewed individually, poured over ice and condensed milk and brown sugar is added. The results are natural, pure and filled with the caffeine we know and love. Where to get in Lowell? Pho Dalat on Chelmsford and Middlesex streets does it v. nicely.