First recorded (as “Toot Tweet (It’s Really Love)”) by Tutti’s Trumpets (1959).
Also recorded (as “It’s Really Love”) by Annette Funicello (1960).
Best-known recording/s by The Tonight Show Band (1962).
From the wiki: “‘Johnny’s Theme’, performed as the theme song of ‘The Tonight Show with Johnny Carson’ for 30 years, began life as ‘Toot Sweet’, a pop instrumental composed in 1959 by Paul Anka and recorded that same year by Tutti’s Trumpets as the B-side to The Camarata Strings’ single ‘Lost In a Fog’ released on Disney’s Buena Vista label. Salvatore ‘Tutti’ Camarata, the ‘Tutti’ of Tutti’s Trumpets and bandleader of the Camarata Strings, was Annette Funicello’s producer at the time. He asked Anka to contribute some songs for Funicello’s first album to follow her work on The Mickey Mouse Club. Anka added lyrics to ‘Toot Sweet’ and published them under the title ‘It’s Really Love’.