Frontera Fresco at Macy's

Was pleased overall with their selections although it was not what I consider a good deal, (not a very liberal meat content and everything was 2-3$ more expensive then it should be for this type of fast food.) it was nevertheless quality. What shocked me was their torta, the bread that they have for the mexican sandwich was phenomenal! I asked the people who worked there if they knew where they got this bread and also emailed rick bayless himself but no reply sadly... Has anyone had the torta here and also know where I might be able to find a similar torta bread as light/airy/tasty as this? Thanks in advance to any replies.

when in a pinch for time, this stand is one of my favorite places in the loop to eat.