What is/are your the most favourite composer s ?

Seems to be a real dearth of French composers here. How about Rameau, Couperin and Lully for Baroque? Also a fan of Henry Purcell, Ralph Vaughn Williams and Schubert.
BTW: I attended a solo recital by Astor Piazzolla on bandoneon.

In the spirit of your post, blasting song after song I would add to many of the above a few 20th century composers of popular music much of which is timeless.

George Gershwin
Duke Ellington
Antonio Carlos (Tom) Jobim
Richard Rodgers

My top 15 
BACH
Josquin Desprez
Mozart
Schubert
Brahms
Purcell
Puccini
Palestrina
Haydn
Janacek
Telemann
Sibelius
Richard Strauss
Byrd
Vaughn Williams

Beethoven, esp. string quartets, piano sonatas, odd-numbered symphonies
J. S. Bach
Mozart
D. Scarlatti 
Bartok (esp. string quartets)
Brahms
Schubert
Mendelssohn
Handel
John Dowland
Telemann
Haydn
Ravel
Debussy
Saint-Saens
Prokofiev
Stravinsky (esp. "L'Histoire du Soldat")
Tchaikovsky
Albeniz
Granados
J. Turina
M. Ponce
M. Castelnuovo-Tedesco