The most common and most likely answer to this crossword clue is the 7 plus 4 letter word DESSERT WINE
D
E
S
S
E
R
T
W
I
N
E
More clues leading to the result DESSERT WINE
Buddy explains!
The straight part
We know that "Diners’ sweet concoction?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case diners’ sweet concoction? = dessert wine.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.