Here's what Wikipedia says about it:
"Misa Criolla was an early non-Latin Mass post-Second Vatican Council. The Washington Post described Misa Criolla as "a stunning artistic achievement, [that] combined Spanish text with indigenous instruments and rhythms". It led to album sales numbering in the millions internationally. Ramírez once told The Jerusalem Post how Misa Criolla was inspired by a visit to Germany after World War II. While there he had an encounter with a group of nuns, which led him to consider writing "a spiritual piece". This would eventually become the Misa Criolla.
The Misa, a mass for either male or female soloists, chorus and orchestra, is based on folk genres such as chacarera, carnavalito and estilo pampeano, with Andean influences and instruments. It is also one of the first masses to be celebrated in a modern language following the lifting on their ban by the Second Vatican Council. Ramírez wrote the piece in 1963–1964 and it was recorded in 1964 by Philips Records, directed by Ramírez himself with Los Fronterizos as featured performers (Philips 820 39 LP, including Navidad Nuestra, remastered in 1994 and released by Philips as CD 526155-2). It was not publicly performed until 1967 in Düsseldorf, Germany, during a European tour which eventually brought Ariel Ramírez before Pope Paul VI. His Mass for peace and justice (1981) is quite famous. Equally famous are the recordings with the solo voices of George Dalaras (1989), José Carreras (1990), and Mercedes Sosa (1999). Plácido Domingo recorded the Kyrie (the first movement of the Misa) with Dominic Miller on guitar (2003)."
YouTube has several versions, including my favorite, this heartfelt performance by Los Fronterizos (about twenty minutes):
I hope you enjoy "Misa Criolla", and that it becomes part of your holiday tradition, too. Merry Christmas, everyone!