Finally, it's quite important to give a sprinkling of table salt to nuts (4,3,3,5)
I believe the answer is:
last but not least
'finally' is the definition.
(I've seen this before)
'of table salt to nuts' is the wordplay.
'of' indicates anagramming the letters (the answer comes from or 'of' the letters).
'table'+'salt'+'to'+'nuts'='tablesalttonuts'
'tablesalttonuts' is an anagram of 'LAST BUT NOT LEAST'.
'it's quite important to give a sprinkling' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for last but not least that I've seen before include "still worth a mention?" , "arranged in ascending order of height?" , "Finally, encouragingly" , "Ultimately still important" , "what Scrabble player could do with italics?" .)