Someone has collected a number of great performances. You have to allow for variable sound quality, tempo and weight of voice, but I'd vote for 2 older voices, Lucia Popp and Edita Gruberova, probably because I fell in love with their voices in the 80s, and Diana Damrau.
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ETA. From the sublime to.... Meryl Streep as Florence Foster Jenkins.
https://en.wikipedia.org/wiki/Florence_Foster_Jenkins
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