Instant gravy bottles? River Cafe?! (6)

I believe the answer is:

bistro

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'cafe?' is the definition.
(I've seen this in another clue)

I don't understand the remainder of the clue.

(Other definitions for bistro that I've seen before include "Cheap restaurant" , "Small bar-cum-restaurant" , "family concern perhaps" , "somewhere to eat" , "Intimate eatery" .)

I've seen this clue in The Independent.

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