In the episode "Biffo Blossoms", when Vinnie was looking for more ways to try and get Biffo to become friendly again, Farmer Organicwheat mentioned baking a cake for his cows. So Vinnie and Rocket baked a Friendship Cake for Biffo and brought it to him in the school cafeteria. He starts looking over the cake with the duo standing beside him and when Scuds and Frankie get his attention, he goes back to his bullying self and smashes the slice on Vinnie's head.
Stills from the original scene[]
Farmer Organicwheat: "I always bakes my cows a cake!"
Vinnie: "Hey Biffo, I baked you a friendship cake"
Rocket: (He pops out of the cake) "Getta! Hey there super-pal-mate-friend-amigo-buddy!"
Biffo: "Mmmm… Cakefully tastetastic, friendly frosted, check out all that, baked goodness"
Scuds: "What do you have there bro?" / Biffo: "Mmm…cake."