Sign off on another order coming from señorita's quarters (8)

I believe the answer is:

notarise

I'm a little stuck... Click here to teach me more about this clue!

'sign' is the definition.
('sign'->'notarize' is in my internal thesaurus and 'ize'->'ise')

'off on another order coming from senorita's quarters' is the wordplay.
'senorita' anagrams to 'NOTARISE'.
However, I'm not clear how the anagram is indicated.

Can you help me to learn more?

(Other definitions for notarise that I've seen before include "Certify (document) officially" , "establish an official record" , "Authenticate" , "Witness official documents" , "Officially attest" .)

I've seen this clue in The Independent.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.