Local mug served up with endless cold and hot soup (6)

I believe the answer is:

borsch

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'soup' is the definition.
(borsch is a kind of soup)

I cannot understand how the remainder of the clue works.

(Other definitions for borsch that I've seen before include "Russian beetroot soup" , "Russian or Polish soup usually containing beet juice" , "Soup made with beetroot" .)

I've seen this clue in the Irish Times (Crosaire) and the Irish Times.

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