What did Hamzy make in this video?

Specifically at 2:12

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[https://www.youtube.com/watch?v=Y42cjZ1Ljow&list=PL13leaWbbPZT3OXaHdHOuNbCtzfFfRbGF&index=1](https://www.youtube.com/watch?v=Y42cjZ1Ljow&list=PL13leaWbbPZT3OXaHdHOuNbCtzfFfRbGF&index=1)

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Is it a pickling or fermentation of some type? I want to try it, but my best google search guesses are coming up blank.

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Thank you!!

by OnlySomewhatSane