Made tart with LSD I cooked without recipe (9)

I believe the answer is:

acidified

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'made tart' is the definition.
The definition and answer can be both related to change as well as being past participle verbs.
Maybe there's an association between them I don't understand?

'lsd i cooked without recipe' is the wordplay.
I cannot quite see how this works, but
'lsd' could be 'acid' (synonyms) and 'acid' is found within the answer.
'i' is present in the answer.
This explanation may well be incorrect...

'with' acts as a link.

Can you help me to learn more?

(Another definition for acidified that I've seen is " Made into something turning litmus red".)

I've seen this clue in The Independent.

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