This place is amazing. Mexican food in Europe is generally piss-poor, at best. Having lived in the southwest US, I don't even try Mexican or Tex-Mex food in Europe.
I was told that this place was good, so we went. Good was an understatement. This place was amazing. The food is cheap, delicious and authentic. Free chips & salsa. Spicy or not, depending on your tastes.
I HIGHLY RECOMMEND the Tijuana fries.
The owner also speaks English, in case you don't speak German.