The most common and most likely answer to this crossword clue is the 6 plus 9 letter word FATHER CHRISTMAS
I've seen this crossword clue in The Guardian
F
A
T
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E
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More clues leading to the result FATHER CHRISTMAS
- Following Mrs Thatcher is a clumsy man with sack
- Following Mrs Thatcher is a flabby man with gifts
- Following Mrs Thatcher is a change for the present supremo
- Priest on holiday who’s sacked for toying with children
- Legend, very generous sort, Mrs Thatcher — as if!
- Benevolent character in recollection of Mrs Thatcher? As if!
- In truth, a parent fine with head of tribe in matriarch: she’s remarkable
- Annual visitor in cavalier charms at first: that man welcomed in
- Provider of child benefits in disorganised firm hates charts
Buddy explains!
The straight part
We know that "Legend, very generous" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case legend, very generous = father christmas.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.