Doughnut, as simple as that.
Although they do not sell the delicious freshly baked doughnut typically found in street festivals, they still do a great job with regular doughnut. And they are not pretentious. Among the options, you can find flavours that could be considered at least questionable, such as Creamy Egg (a chocolate doughnut with a creamy egg hidden in it). However, they really do a great job with the basic and, as a result, the end product are usually very good.
My favourite flavours are Death by Chocolate and Salted Caramel (they have version with and without filling).
It definitively worth a visit! (even though the coffee is not good)