That sounds too good to be true. Why aren't hundreds of entrepreneurs doing that every day (which would either drive up the cost, or drive down the profits?)
You need to have something original. Something that the locals cannot normally get. Western food is a big big seller here.
Im not joking when I say that Chili's here does close to US10-15K on a weekend.
Right now there is NO Mexican restaurants here (actually there are 2 - but they are run by a local chinese guy and they suck - still he makes good money) - but like 300 Italian places. There is perhaps 20 German restaurants.
Cajun food would do great here as well.