American writer's most important piece on you (10)

I believe the answer is:

kingsolver

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

'american writer's most important' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'piece on you' is the wordplay.
'piece' becomes 'king' (king is a kind of piece).
'on' means one lot of letters go next to another (in a down clue, letters appear on others).
'you' becomes 'solver' (the solver of this crossword puzzle!).
'king'+'solver'='KINGSOLVER'

Can you help me to learn more?

I've seen this clue in The Independent.

Want a hint initially instead of a full solution? Install my app