Rainbow Rice Krispies Treats

Don't ask me what madness led to this. All I know is, I had a huge bag of marshmallows to use up (kindly donated by Frickin'LaserBeam Man) and an urge to do something with rainbows. Again. Since I've used up my s'mores quota for the moment I felt the need to make some Rice Krispies Treats! (Or Rice Bubble Bars/LCMs for the Aussies. I still don't know what LCMs stands for...) So why not make them all the colours of the rainbow?! And as I was stirring up a pot of bright purple melted marshmallow all I could think was, 'This is so disgusting.' What can I say, I'm in a crazy baking phase.

I'd seen other versions of rainbow rice krispies squares, but all the different colours were usually mixed together. I wanted to do something different, by creating super thin layers of each colour stuck on top of each other. And the best part, hiding it under a layer of regular old plain rice krispies so if you looked from the top (see above photo), you'd be none the wiser. Then you cut into it and...

Tada! So bright! So vivid. (Yes I still love the Double Rainbow meme) Isn't it preeeettyy??? It looks even cooler when you put those two pictures right next to each other, look:

[Click here for the full-sized version]

And before I get any remarks about the evils of food colouring, use natural food colouring or don't make it at all. This was for fun! I was nervous to see if this idea was actually possible, it all sounded so fiddly and messy having to do each layer separately and spreading it out in a thin layer. But after a couple of layers I really got into the swing of things, the trick is to work really quickly while pressing it into the pan, using a piece of baking paper to help flatten out each layer. The most annoying part was having to wash out my saucepan after each layer. Use a non-stick pan if you can, the caked-on bits were a total pain to scrub off.

This doesn't really count as baking since it's just heating and mixing up ingredients in a saucepan but for something so simple it's a ridiculously satisfying snack. I know for sure that kids would love it because it really brought out the silly kid inside me. Plus the fact that I left the butter sitting on the heat too long for a few of the layers it ended up being browned butter rice krispies, which is pretty much the best mistake I've ever made. I mean, look at these ones on Smitten Kitchen, how amazing do they look??

There was some debate about if I should top these squares with a plain white layer of Rice Krispies or not. It might be unnecessary but in the end I think it was the right choice to have the white layer, to cheekily hide all the rainbow colours underneath (it made me think the most fantastic cake in existence, Whisk Kid's rainbow cake). Plus the having the red layer as the top layer looked a bit creepy.

Rainbow Rice Krispies Treats
(Adapted from the Original Treats recipe, makes 25 squares)
1 x 400g pack of marshmallows (I used white & pink ones), about 7 cups
100g butter (approx 7 tbsp)
7 cups rice krispies/rice bubble cereal (approx 210g)
Food colouring (I used mostly liquid, though I did have some Wilton paste as well, use whatever you prefer)

Grease and line a 20cm square cake tin with baking paper. Place about 1 tbsp (14 g) of butter and one cup of marshmallows (approx 60g) in a medium saucepan and place on low heat, stirring until completely melted. Add purple food colouring and 1 cup of rice krispies (approx 30g), take off the heat and stir until well coated. Using buttered spatula or a piece of wax paper, evenly press mixture into the bottom of the lined tin, trying to make it as even and well-packed as possible. Repeat with the same amount for each other colour; blue, green, yellow, orange and red, pressing each layer tightly over the top of the previous one in the pan. Optional: top with another layer of with no colour added, making it 7 layers in total.

Set aside to cool and set. Lift out of the cake tin and cut into 25 square pieces using a long sharp knife. Best eaten on the same day but can be stored in an airtight container lined with baking paper in the fridge. Can also be frozen for up to 6 weeks.