Bilaskhani Todi is a Hindustani classicalraga. It is a blend of the ragas Asavari and Todi, and has a close affinity with Komal Rishabh Asavari. Though being named Bilaskhani Todi, it does not belong to the ThaatTodi, but it belongs to the ThaatBhairavi. It is named Bilaskhani Todi because of the Meend used while singing the notes 'Ga' and 'Re', a common feature of the Raag 'Todi'.
Theory
The Hindustani classical raga Bilaskhani Todi is an example of the flaws of the Bhatkhande thaat system because it is classified under the Bhairavi thaat based on the notes it uses, but it is actually a type of Todi, and permitting any Bhairavi during a performance kills the raga.[1]
Legend has it that this raga was created by Bilas Khan, son of Miyan Tansen, after his father's death. It is said that while trying to sing Todi, his father's favorite raga, in the wake of his father, Bilas was so grief-stricken that he mixed up his notes. That gave birth to this raga, and that Tansen's corpse moved one hand in approval of the new melody. (There is a similar legend, differing only in detail, about Tansen's Todi.)
Bor, Joep (ed). Rao, Suvarnalata; der Meer, Wim van; Harvey, Jane (co-authors)The Raga Guide: A Survey of 74 Hindustani Ragas. Zenith Media, London: 1999.