We went to Tia's on a Saturday around 6:30pm and it was pretty empty. A few things I loved:
The whole place is family run. The owner made sure to stop by every table to see how our food and experience was, and made sure we were enjoying ourselves. Her son is one of the line cooks in the back, her (I think) daughter is the manager, etc. It's great to see a whole family coming together to open up a new business.
The real reason for my 3 stars was for my main dish. Granted, I did not get any tamales, which is what Tia Shorty's is known for (they've been selling their tamales in PHX for many years and recently decided to open a restaurant due to that success). I got a taco salad that was really just incredibly bland. This place prides itself on authentic Mexican fare, and it just wasn't that for me.
I will say that the nachos we had as a starter were delicious. They use their queso to cover them and they were ridic. I would have gladly had those as my meal!