Mission in Kohala Mountains (5)
I believe the answer is:
alamo
'mission' is the definition.
(famous mission and siege from the Texas revolution)
'in kohala mountains' is the wordplay.
'in' says the answer is hidden in the clue.
'ALAMO' can be found hidden inside 'kohala mountains'.
(Other definitions for alamo that I've seen before include "The red planet" , "Mission building in Texas, site of famous siege by Mexico" , "Where Davy Crockett died, 1836" , "Scene of massacre in Texas" , "Fort in San Antonio, once famously besieged" .)