それいけ！アンパンマン パンタンと約束の星
Soreike! Anpanman: Pantan to Yakusoku no Hoshi
Comedy · Fantasy
Pantan is a red panda who seeks to find the treasure thought to be in a rainbow star in the night sky, in order to keep a promise made to an adventurer long ago. When Pantan and Anpanman encounter each other, Anpanman lends his abilities to help out Pantan.
Synopsis excerpt via AniList, originally from Anime News Network.