Naked Rainbow Cake with Race Car Track

Birthday boy Ryan's current fave toys are his Tomica cars. His mummy wanted a simple cake with a race track on it, so she could top it with a few new cars. I said why don't you just use the ones he already has? He has so many. She said that the cars are so dirty that even she wouldn't eat a slice of cake if she put those ones on. Haha. Lucky Ryan got 4 new Tomica cars in addition to all his birthday presents!

Naked rainbow cake

Ryan's mummy also wanted an un-iced cake where the rainbow layers would show through. I was like, oh you mean a naked rainbow cake? She's like, is that what it's called? Haha. I dunno. It just popped into my head. Maybe it really is called a naked rainbow cake. 

ROYGBV - six rainbow colours!

So I baked up two recipes of vanilla bean butter cake in my trusty IKEA rectangular pan, splitting each recipe into thirds to get six ROYGBV rainbow colours. Forget indigo. What colour is indigo really? 

love the rainbow reflection on the cake board

At first I thought that the cake would be less than 3" tall since the layers were pretty thin, but after sandwiching vanilla bean German buttercream (aka crème Mousseline) in between each cake layer, the cake turned out to be 4" tall! I am so loving German buttercream because it starts off as a custard base, made with 12 egg yolks! Great way to use up all those yolks I always have kicking around in my fridge from making Swiss meringue buttercream and macarons!

race track ready for cars

Naked cake is more challenging than it sounds. I actually had a tough time trying to keep the edges neat while stacking the layers. I usually just slather on buttercream and use a scraper so smoothen everything out. Not so with a naked cake! No hiding cracks at the edges or uneven piping here. 

race track naked rainbow birthday cake

I cut out a large black fondant oval for the race track and accented it with white stripes. To finish off the cake, I used a grass piping tip for the grass all around the track. A couple of fondant stars, a happy birthday message and the birthday boy's name and this cake was all ready for the party.

view from the top

The birthday boy looks pretty pleased with his cake! I think he was more happy to see the 4 new Tomica cars. Haha. He took a while blowing out the candle (even though it wasn't a trick candle!) but he eventually got it. The boy to his right may have helped... haha. Happy 6th Birthday, big boy Ryan!

Happy 6th Birthday, Ryan!

make a wish!

tall six-layer rainbow cake

yum yum. double vanilla bean cake