Darasse was born in Toulouse (Haute-Garonne) into a family of musicians (his mother, Renée-Marie Darasse-Laroyenne, was an organist) in 1964 and is a namesake of Saint Francis Xavier.
In 1976, after a serious road accident, during which he lost his right arm (which he was successfully transplanted without being able to regain his motor skills), he had to put an end to his career as a concert performer.
He then devoted himself to teaching the organ, as well as composition, with among other things "Instants éclatés" in 1983 for the Orchestre national du Capitole de Toulouse.
He died prematurely of cancer in 1992 in Toulouse, leaving an opera adapted from Oscar Wilde's the Picture of Dorian Gray unfinished.
Darasse had close friendships with Antoine Tisné and Iannis Xenakis, and he gave the French and German premieres of the latter's only organ work Gmeeoorh (1974).