The most common and most likely answer to this crossword clue is the 9 plus 5 letter word WORCESTER SAUCE
I've seen this crossword clue in The Times
W
O
R
C
E
S
T
E
R
S
A
U
C
E
More clues leading to the result WORCESTER SAUCE
Buddy explains!
The straight part
We know that "Blend correct, as we use anchovies in it" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case blend correct, as we use anchovies in it = worcester sauce.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.