Expensive marinade (5)

I believe the answer is:

steep

This clue is a double definition.

'expensive' is the first definition.
(I've seen this before)

'marinade' is the second definition.

(Other definitions for steep that I've seen before include "Difficult" , "not reasonable" , "Soak thoroughly - precipitous" , "Stiff - thoroughly wet" , "Unreasonably dear - soak" .)

I've seen this clue in The Guardian and The Times.

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