The most common and most likely answer to this crossword clue is the 7 letter word PAVLOVA
I've seen this crossword clue in The Sunday Telegraph
P
A
V
L
O
V
A
Buddy explains!

The straight part
We know that "Sweet/dancer" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sweet/dancer = pavlova.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.
What does PAVLOVA mean?
PAVLOVA noun- (foods) A meringue dessert usually topped with fruit and cream.