Troublesome thing, duck sauce (5)

I believe the answer is:

pesto

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'sauce' is the definition.
(pesto is a type of sauce)

'troublesome thing duck' is the wordplay.
'troublesome thing' becomes 'pest' (I have seen 'Annoying thing' mean 'pest' so perhaps 'thing' could also mean 'pest'. I am not sure about the 'troublesome' bit.).
'duck' becomes 'o' (resembles zero - 'duck' in cricket).
'pest'+'o'='PESTO'

Can you help me to learn more?

(Other definitions for pesto that I've seen before include "Sauce of basil, pine nuts, etc" , "Green sauce" , "Saucy work" , "Pasta sauce mainly of basil and cheese" , "Sauce made of basil and cheese" .)

I've seen this clue in The Independent.

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