Rainbow Cake 

When someone shoves fruity pebbles up their partners butt hole, and then jumps on their stomach with full force. This causes them to shit it out.

Mike: Hey! Get those fruity pebbles away from my butthole!
Steve: Don't worry bro, I'm not making a Rainbow Cake.

Rainbow Cake by Gurwie March 26, 2010

Rainbow cake 

This cake is perfect for birthday parties and other festive events. It has five different colored and flavored butter layers (strawberry, orange, lemon, lime, grape) with cream cheese icing and rainbow sprinkles. You can find the recipe at rainbowcakerecipe.com

Hey mama, make me a rainbow cake!

Rainbow cake by alexnicks December 15, 2014

Over-The-Rainbow Cake 

A frosted "space cake" (marihuana cake), covered with Molly (MDMA powder), and with liquid LSD dropped onto the cake.

I gave Mary Beth a slice of Over-The-Rainbow Cake for her birthday, and she took off all her clothes and swam through the snow for an hour!

Over-The-Rainbow Cake by Tom, The Rhinoplastic Surgeon November 28, 2011

rainbowcake 

A situation "goes rainbowcake" when a perfectly innocent, frivolous conversation suddenly explodes into discord and strife; particularly when it becomes a political argument that never seems to end. While applicable in real life, rainbowcaking most commonly occurs in internet threads. The correct response when someone begins to rainbowcake you is to say "until it's frozen!" It spawns from the great rainbowcake apocalypse of 2014, which can be seen on The Concourse by googling "rainbowcake apocalypse."

The discussion about the relative cuteness of puppies versus kittens went all rainbowcake when Harriet called Abagail's viewpoints on the fluffiness of her tail taoist communist propoganda perpetrated by the lamestream media.

rainbowcake by mrsroboto August 9, 2014