In England I ran a food stall in one of the local markets (tapas style cuisine) and wanted to see if I could replicate here in Zurich.
I get the feeling its a little more difficult, as other than the viaduct I cant think of a "foody market" and I have been surprised by the lack of street vendors / carts.
A quick search of the forum turned up this thread from a few years ago: Food Street Cart Vendor
which lowers my hopes somewhat! Does anyone have experience in the matter or suggestions of where to start?