"Working Up an Appetite" is a playful and energetic theme in F Mixolydian mode and 4/4. Its rapid intro sets the tone and key with an immediate trill. The jazzy melody, played by a saxophone, bears resemblance with other themes in related keys: "Stage: Comical" and "Care for a Refreshment?". The end of the melody is dragged out and joined by bells, while the second phrase brings in brisk synths. The melody repeats, and its second phrase resolves after a chromatic transition to a full perfect cadence. The percussion becomes significantly more quiet for the second, cheekier section with a smoother melody but more diverse instrumentation, including cartoonish sound effects. As breezy synths slowly take the lead, a descending modulating sequence plays out, abruptly ended by a dominant fanfare. A variation of the main melody is played by a vibraphone and electric guitar, now quiter and in a more orderly fashion. As if preparing another resolution, a smooth, more lyrical saxophone and electric guitar section becomes a rising modulating passage tinged with minor harmonies. Fanfares follow in a concluding cadence, ending with a trill similar to the intro's. Synthesizers and a piano provide a brief ambient intermission before the main melody returns, full of energy and looping the track.
