Taco's Taco's everywhere!
When searching for the best Taco in Austin, make sure to ask the locals where they prefer to go. 9/10 times they will say Veracruz, and honestly it was a wild ride to flavortown. I ordered a chicken and a fish taco, both were incredible, simple, and delicious. My friend Elia and I ate them outside in the parking lot (because Veracruz is a bus turned restaurant) with bright pink umbrellas and even louder blue picnic tables surrounded by local Texan flora and fauna.
When in Austin, go to Veracruz - simple as that!