What does the cryptic crossword clue "Mashed smashed — that's it! (2,4)" mean?

The definition is "–". The wordplay uses an anagram. anagram of MASHED ("Mashed") [anagram: "smashed -"] = EMDASH The answer is EMDASH.

Mashed smashed — that's it! (2,4)

Guardian Cryptic #29206 | 21 Down | 2023-10-20 flower