What does the cryptic crossword clue "Mark very particularly chopping cabbage up in one go (2,4)" mean?

The wordplay uses a reversal. NB (synonym="nota bene , ‘mark very particularly’") in ELOC (synonym="ELOC") = ENBLOC The answer is ENBLOC.

Mark very particularly chopping cabbage up in one go (2,4)

Guardian Cryptic #29521 | 20 Down | 2024-10-23 flower