MySQL my.ini file for time-zone setup

[gal67]

OSX
1.8.3-5

I'm following instructions that tell me to do the following:

in the XAMPP Control Panel, next to MySLQ, click on ‘Stop’ and wait for MySQL to shut down.
Choose ‘Config’ and select ‘my.ini’. At the end of my.ini, add the lines:
(changing {your timezone} to your actual time-zone, of course!). Note that here ‘time-zone’, has a hyphen in the middle.
Save and close ‘my.ini’.

I can't find the my.ini file
The my.cnf file doesn't have a time-zone listed

How do I set the MySQL time-zone?