Give an amount that's generous (8)
I believe the answer is:
'generous' is the definition.
(similar in meaning)
'give an amount' is the wordplay.
'give' becomes 'hand' (synonyms).
'an amount' becomes 'some' ().
'that's' is the link.
(Other definitions for handsome that I've seen before include "large", "Attractive, liberal", "beautiful", "Attractive in a strong, imposing way", "Good-looking or generous".)