Mushroom feast (6)

I believe the answer is:

spread

I believe this is a double definition.

'mushroom' is the first definition.
(mushroom can mean to spread or grow)

'feast' is the second definition.
(I know that feast can be written as spread)

(Other definitions for spread that I've seen before include "Extend -- feast" , "we hope to avoid in middle age" , "Courses" , "butter?" , "Rancher's property - sumptuous meal" .)

I've seen this clue in The Guardian.

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