You don't need more than three days in Austin. Seriously, you don't and you can still have an amazing food experience. Trip Advisor and Yelp will have some great recos but after multiple visits to the city, here's what I would recommend to eat and drink for the long weekend.
Best hidden gem | Vera Cruz All Natural Food Truck. Locals restrain to share with his new favorite taco truck, and there is good reason why. Be sure to get aguas frescas when you get tacos. My favorite? Fish tacos and pineapple aguas frescas.
Best new hotspot | Temuri Tatsui-Ya: Texan and Japanese fusion cuisine is an unexpected and playful take on BBQ. Delicious food with Michelin Star service. No wonder they are nominated for a James Beard award.
Best BBQ | La Barbeque: Great local BBQ with a reasonable wait. Locals and tourists alike will visit this BBQ join. Bonus points, you can go inside to grab a beer on tap and head back outside while you wait in line. Avoid the 3-4 hour wait at Franklin's as you aren't guaranteed food and you have to BYOB. Note there are two lines, one for drinks and one for BBQ.
Best margaritas | Matt's el Rancho: Be sure to visit during happy hour as their drinks are 50% off. But the price isn't why you come here. It's for the atmosphere and their "top shelf margarita blended margaritas"; our favorites are the mango and prickly pear. Also recommend that you get their queso to go with their chips and salsa.
Best coffee with the view | Mozart's Coffee and Roaster: Avoid Caroline in downtown Austin and head to Mozart's for some local roasts and yummy desserts on the water. The service is great and though you're surrounded by alot of university students cramming for finals, it's quiet and you can actually hear what your partner is saying.
Best place for sour beer | Jester King Brewery: This is probably the best place for a brewery. The view is gorgeous and the plethora of benches under beautiful trees where you can sip a flight or two of beer makes you feel like you're in a fairytale. The local woodfire pizza coming from the neighboring farmhouse will definitely make you hang out here for the afternoon. Note: They specialize in sour beer, not alot of diversity outside of this. You can still visit the 'known' places like Torchy's and Chuy's (be sure to hit up Chuy's on a Tuesday for their fried, stuffed avocado) and you'll still have a great time and good food.
Avoid the following:
La Condesa: Despite it's great service, the food and drink are overpriced. Can you say $19 cauliflower steak?
Caroline: The baristas here hate life and their job. They let a $8.95 cup of hot Bulletproof coffee sit there for over 10 mins while trying to open a container and then pass over the now cold cup of coffee over to you. Even worst, when they run out of large plastic cups, they don't tell the customers, but still charge for the large cup. All you get is a "sooorrry." Save your money and walk across the street to Starbucks. At least you know the quality is consistent and the drink will be hot.