Generous giving (8)
'generous giving' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for largesse that I've seen before include "Generous alms" , "Generosity in gift-giving" , "Generous giving" , "Magnanimity, munificence" , "Money or gifts generously given" .)
(Other definitions for largess that I've seen before include "Generosity" , "Bounty" .)