The Mushroom Derby is a race that takes place on Yo'ster Isle in Super Mario RPG: Legend of the Seven Stars. Mostly, only Yoshis participate in the Mushroom Derby (however, the Yoshis may have riders accompany them during the race). The steps in the race have to follow the music that is playing in the background. A Yoshi can boost its speed with a Yoshi Cookie. The winner also gets cookies rewarded.
In the ending sequence of the game, Croco can be seen racing with Yoshi in the Mushroom Derby.