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Empty sandwich generates livelihood (5,3,6)

Ross

I believe the answer is:

bread and butter

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'livelihood' is the definition.
(synonyms)

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(Other definitions for bread and butter that I've seen before include "pudding" , "basic course" , "basic source of income" , "fare" , "rather monotonous diet" .)

I've seen this clue in The Daily Express.
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