Add more solids to kitchen stew (7)

I believe the answer is:

thicken

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'add more solids' is the definition.
I can't judge whether this defines the answer.

'kitchen stew' is the wordplay.
'stew' indicates an anagram.
'kitchen' anagrammed gives 'THICKEN'.

'to' acts as a link.

Can you help me to learn more?

(Other definitions for thicken that I've seen before include "Make more viscous" , "(Of a plot) become more complicated" , "Become more dense (as plots do)" , "Make dense" , "Clot" .)

I've seen this clue in The Globe and Mail.

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