Sanitarium dish, not an Italian dessert (8)

I believe the answer is:

tiramisu

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'italian dessert' is the definition.
(I've seen this in another clue)

I don't understand the remainder of the clue.

(Other definitions for tiramisu that I've seen before include "Italian sponge dessert" , "Arenaceous material" , "Dessert soaked in alcohol" , "I must air the Italian dessert" , "Italian dessert with coffee and liqueur" .)

I've seen this clue in the Sydney Morning Herald.

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