Concerning your analysis of El Mirador Taqueria, in your second paragraph you admit that it is a Mexican Restaurant. I was in Mexico for 17 months and never saw ground meat. Hamburger is ground up meat that is not otherwise marketable. Hamburg is in northern Germany and if you want hamburger you might try a northern German restaurant. Tell them you want real buns not tortillas.
You complain that the sauce was hot, tell them you want real ketchup. I assume ‘Lenkersdorfer’ comes from northern Germany where they like empty calories. Southern Germans like it a little spicier, so you better hope your cook isn’t from Munich, because if she slips a piece of Jagerschnitzel in on you, you might wish you had gone to a real Mexican restaurant.
You say your wife really like her meal, maybe she likes real Mexican food. (?)