In all of the responses, I've only seen one piece of wisdom, and that would be Crossbones' suggestion of Pho. If you are fortunate enough to live in Austin, TX, my first suggestion would be Pho Natic and secondly Pho Saigon (both owned by same family).
Before you embark on your quest for cosmic balance by way of ingesting Vietnamese cuisine, let me encourage you to drop by whole foods, sprouts, natural grocers, or the like, and pick up a liter of coconut water (not milk). Drink that, give it an hour, drink a 5 hour energy, and then nurse another liter of coconut water until you feel right.
Coconut juice is a miracle that will set you right faster than anything else I've ever tried. It's knocked the slag off of a salty margarita hangover faster and more effectively than anything.
If you are the type that HAS to have a little hair of the dog, may I suggest making an avocado margarita with a HIGH quality tequila. Basically a frozen margarita with a whole small or large half avocado blended in. The combination of fat and electrolytes will set you straight in a hurry. And before you make yuck faces, try it. I had one at Curra's, and have been making them ever since. Oh, and DON'T use Margarita mix. Use LIME JUICE. If you need it to be sweeter than the lime juice will allow, throw in a splash of B-grade maple syrup as it is FULL of vitamins and minerals.
Trust my 38 years of experience. I have lived hard, worked hard, and played way too hard, and what I have shared represents my personal treasure trove of relief from several "leaving Las Vegas" episodes of drinking.