This world premiere recording was released earlier this year but it completely slipped by me. Performed by the Erik Westberg Vocal Ensemble, conducted by Erik Westberg. Composed in 1920-21 and is considered the composer's last great work.
https://www.amazon.com/Missa-Solemnis-Erik-Westberg-Vokalensemble/dp/B08YDP9Y9L (https://www.amazon.com/Missa-Solemnis-Erik-Westberg-Vokalensemble/dp/B08YDP9Y9L)
Yes, I'd spotted this too. Thanks.
https://www.prestomusic.com/classical/products/8906329--hallen-missa-solemnis
The piece failed to make an impression on me except for the first few minutes of Agnus Dei. There is a hint of sadness yet solemnness in these moments, and while not representing a vast soundscape, it does give that pious atmosphere that you would expect in a cathedral.
I prefer his Christmas Oratorio, but that may be because of the orchestral backing which I feel is missing here. The addition of a piano helps to give it some depth, though. It's kind of funny reading that he composed this with as little instrumentation as possible for strictly practical reasons.
This is an absolutely glorious, fully romantic work with an extraordinarily rich vein of melody. There is immense tenderness here as well as great power. Grab it while you can!