I'm in the USA, so I take "Mexican food" for granted. I would imagine there aren't too many Mexican restaurants in Greece, so congratulations for finding one!
Here in the US, arguments start all the time about "authentic" Mexican food vs. Mexican food that is US-influenced. "Tex-Mex" is one style - restaurants that serve things like fajitas and large burritos are likely Tex-Mex, as opposed to authentic Mexican food.
Yours, judging from the photos, might be closer to authentic Mexican food than ours.
I hope you'll go back - if you enjoyed it - and keep sharing your photos!
There are mexican restaurants in Greece but Ι didn't go again at a mexican restaurant. However, thanks a lot :) :)