Archbishop Salvatore J. Cordileone commissioned this mass for the occasion of the Solemnity of the Immaculate Conception and celebration of the Feast of Our Lady of Guadalupe on the Saturday before December 12th, which happened to be Dec. 8!
EWTN provided live broadcast of the mass which is preserved on the link above. On that same page, please enjoy the interview of the archbishop with Fr. Mitch Pacwa, in which Archbishop Cordileone explains the Benedict XVI Institute for Sacred Music and Divine Liturgy whose two pronged effort serves teaching chant and sacred music to schools and providing parishes with resources to improve their liturgy and music.
The composer is Frank La Rocca and you can find his beautiful sacred works on YouTube.