Dessert heads for diner least expecting pool of liquid (6)
I believe the answer is:
puddle
'pool of liquid' is the definition.
'puddle' can be an answer for 'pool' (synonyms). I am not sure about the 'of liquid' bit.
'dessert heads for diner least expecting' is the wordplay.
'dessert' becomes 'pud' (short for pudding).
'heads for' says to take the initial letters.
The first letters of 'diner least expecting' is 'dle'.
'pud'+'dle'='PUDDLE'
Can you help me to learn more?
(Other definitions for puddle that I've seen before include "A small pool as of rain" , "Standing rain water" , "Small amount of standing water" , "Small amount of standing rainwater" , "Small pool of rainwater" .)