I remember "Halbgefrorenes"[1] as one of the main source of income for many restaurants and Cafés in the former DDR(GDR). Second recipe to generate nearly unlimited profit was Soljanka[2].

[1] https://de.wikipedia.org/wiki/Halbgefrorenes (german)

[2] https://en.wikipedia.org/wiki/Solyanka (english)

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