The operatic quartet - who recently worked with Nicole on a rendition of 'Cats' track 'Memories' for their new album 'A Musical Affair' - admitted fancying 'The X Factor' judge and hinted at a live collaboration with the stunning brunette.
Baritone Carlos Marin said: ''Nicole is really hot, she's not only hot in photos and the good thing is she sings amazing, I was really surprised at how well she fits in the musical theatre. It was great singing with her.
''It would really be amazing to do something with her, a show with her ... something else and a show.''
The singers - whose new album also features duets with Barbra Streisand, Michael Ball and Kristen Chenoweth - even talked of the prospect of an unusual collaboration with 'Wrecking Ball' singer Miley Cyrus, who shocked audiences with her controversial appearance at the MTV Video Musica; Awards earlier this year.
Tenor singer Urs Buhler said: ''I think we should do something with Miley Cyrus! Some kind of combination.''
'Smalls Change (Meditations Upon Ageing)' arrives in April.
The two awards have made for a great 72nd birthday present for the country music icon.