Schrebergarten is a small restaurant in Mainz' town centre.
They serve filled potatoes called Kumpir (a turkish tradition), salads, homemade lemonade and soups.
The menu is really small but to my mind, this is positive and represents that the food they serve is fresh.
I tried the vegan kumpir version "veganistan" which was delicious and new to me.
Try this place, it's lovely :)
Cons: staff seems to have little experience