Coffees from Latin America is usually very easy to handle. As they are grown at altitudes from 1400-1700m. The cellular structure is more uniform and makes it easier to calibrate when dailing in your espresso shot.  

At this altitude the cellular structure is uniform. And very little adjustments have to be made. The challenge often appears during the process method, whether is an anaerobe or natural coffee. And whether you want to highlight acidy or sweetness based on the process method. 

A washed coffee is usually more chocolaty which i will recommend extrating at 27-29 sec.

I usually extract between 25-27 sec but it also excellent when extrating at 27-29 sec. 

Dose 21 g dobb shot
Extraction 26-29 sek
Target mass in weight/liguid 40 g.
Extraction rate 21/40= 0,52%

The dose is calculated using a 20g VST porta filter.

Min dose is 19g/ and Max dose 21 g. pr dobb espresso.