What is the name of the first Looney Tunes short to be produced in color?

The first Looney Tunes short produced in color was The Hep Cat.

Directed by Bob Clampett, The Hep Cat was released on October 3, 1942, and was the first Technicolor Looney Tunes short. It centers on a lovestruck cat whose attempts to court a female cat are repeatedly disrupted by Rosebud, a dog who chases him through an abandoned lot and around a fire escape. The fast pacing, musical gags, and surreal visual tricks reflect Clampett’s energetic style.

The Hep Cat is often confused with earlier Warner cartoons that were produced in black and white or with color films from the related Merrie Melodies series. The wording matters: The Hep Cat is identified specifically as the first Technicolor Looney Tunes short, while “Looney Tunes” and “Merrie Melodies” were companion Warner Bros. series with different release histories. The short’s music was composed by Carl W. Stalling, and Mel Blanc voiced the Hep Cat. Later television prints sometimes altered its title cards, creating additional cataloging confusion.