Where I work in Mexico we have a teacher who is from Uganda, she grew up speaking English and lived and studied in the UK, as far as I know. I have also met a lady from India who held a good job at a university. If you want to try teaching for the experience and to see if you like it you shouldn't have too much trouble finding a job in Mexico or Central America, and they won't hold your nationality against you.

Without certification or more importantly, experience, you probably won't find a top job, but at least something to see if you like it enough to go to the time and expense of further education.

If you can afford it the best bet would be to take a vacation here and ask around, read the local job ads, etc.