[4] Matt Collar reviewed the album for Allmusic and described it as "eclectic, playful, and often beautiful" highlighting the "ruminative version" of John Lennon's "Oh My Love" and the "positively swoon-inducing" "Je te veux" in which Cécile McLorin Salvant "draws upon the languid, bittersweet influence of Billie Holiday, while always keeping a smile in her voice".

Collar concluded that "Terrasson's original compositions reveal a passion for melody and groove, paired with an adventurous, flowing, stream-of-consciousness post-bop aesthetic that ultimately makes Gouache a pure joy to hear".

[11] Conrad noted that the "prancing groove" of "Rehab" is "interrupted by ominous crashes" and highlighted trumpeter Stephane Belmondo's contribution on "Mother".

He creates some truly touching and delicate moments here, in particular a version of Erik Satie's Je te veux, with vocalist Cécile McLorin Salvant, and a quietly disturbing treatment of Amy Winehouse's Rehab.

[12] "Baby" was described by reviewers both as a "jaunty sleigh ride of song, with a euphoric '70s R&B ballad midsection" and as "vacuous a ditty as you've ever sat still for" that Terrasson "speeds...to a blur on acoustic piano and hammers it on Fender Rhodes.