수작이 · 수작을
excellent work, fine piece
Example
올해 영화제에는 수작이 많이 출품되었어요.
Many excellent works were entered in this year's film festival.
Word parts
수 outstanding+작 work
Literally 'outstanding work.'
Good to know
Don't confuse it with 수작 'ploy, come-on' (酬酌), as in 수작을 부리다 'to play tricks.'