Chihuahua allows five different spellings, that I could see:
chapati,
chapatti,
chappati,
chupati and
chupatti. But, as people have mentioned, some dictionaries offer additional variants, including
h and/or
y.
Crumbs!
The only version we treat as common is
chapatti. I believe it should be brought into line with the other versions, and made rare.
It's probably not surprising the issue hasn't come up before, because there's only one nine-letter word seed that would allow the double-T version:
apathetic. I'm surprised you could be bothered raising the matter, RM.
Pronunciations seem to be all over the place, too. Go to the
Free Dictionary entry for chapati and click on the US and UK flag symbols, and the little speaker within the definition. Now try the Union Jack in the
chapatti entry.
In Australia we seem to use both the
chapati and
chapatti spellings, but with a slight preference for the latter.