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Kit Kat Birthday Cake


I’ve made a lot of birthday cakes in my day, but I’ve never made one for a kid. Now that I live in the same country as my two nieces, the job of “birthday cake-maker” fell to me this past weekend.

“How difficult can that be?”, you might be wondering. Well, as the “auntie who can cook” I had certain standards expected of me. The cake couldn’t come from a box, but it’s for a kid, so it should probably taste like one that comes from a box. It couldn’t be smothered in cream and fruit; that wouldn’t be fun enough. It needed a bit of a “wow” factor, since, until the niece in question spends the weekend with us next week she wouldn’t be getting a present.

Anyway, I love putting unnecessary pressure on myself. Can you tell?

In the end, I decided to make things a bit easier. We’ve all seen the Kit Kat Cake on Pintrest, right? It looks pretty impressive, but from a cake-maker’s perspective it’s not that difficult to make. Just a basic cake, iced and then covered in Kit Kat sticks and M&M’s. Tie a ribbon around the Kit Kats when you’re done and you have a very festive cake, perfect for a candy-loving ten year old.

I thought a chocolate cake covered in chocolate icing and chocolate candy bars might be a bit “overkill”, so for the cake I made Smitten Kitchen’s Best Birthday Cake. It was perfect – the end result actually tastes like a yellow cake mix from Duncan Hines and the like. Instead of using her sour cream chocolate icing (something I would love if making the cake for myself, but not so sure for my niece), I made a basic chocolate buttercream using icing sugar, cocoa powder, heavy cream, vanilla and softened butter.


I should mention that Smitten Kitchen’s recipe makes a BIG cake. If all that batter went into two 9 inch layers, it wouldn’t work for the Kit Kat cake. When the Kit Kats are lined around the cake, you want them to be a few centimetres higher than the top of the cake. Otherwise, the M&M’s would have nowhere to go, and that would be very sad. Instead, I used two smaller sandwich tins. This recipe will make three layers of sandwich-sized cakes. I used two layers for the birthday cake and with the third, made a more “adult friendly” cake with the leftover frosting and Kit Kats.

This cake is absolutely delicious on it’s own. Simply masked in a buttercream, it’s moist and tastes of eggs, sugar, vanilla and has a tang from the buttermilk. With the Kit Kat’s and the M&M’s I found it way too sweet. The kids absolutely loved it, though, and it was well worth the effort!


Kit Kat Birthday Cake


Two sandwich-tin layers of Smitten Kitchen’s Best Birthday Cake

3 1/2 cups icing sugar

1 cup good quality cocoa powder

1 cup softened butter

1/2 cup heavy cream

1 tsp vanilla

40 Kit Kat sticks (make sure you buy extra, though, to account for breakage)

2 large bags of M&M’s

Ribbon, Bows

Decorative Candles


  • Once the two layers of cake have completely cooled, place one layer on a disposable cake plate (you can get them at the dollar/euro store or Bulk Barn in Canada). Place the cake plate on a cake turntable, if you have one.
  • Mix the frosting with a hand mixer or stand mixer, making sure it’s smooth and free of lumps. Put 3/4’s of a cup of frosting on the first layer. Using a palette knife, spread the frosting evenly over the top of the first layer. Sandwich with the second layer.
  • Mask the cake with the rest of the frosting, starting with the top of the cake and spreading evenly over the sides (the turntable really helps you get an even layer of frosting, and the palette knife helps sculpt the frosting around the edges – both are great investments if you love decorating cakes).
  • Time for the Kit Kats: use a kitchen knife to separate the sticks. If you break them by hand it will look rough and uneven.
  • Carefully stick the Kit Kats around the edge of the cake. Some people leave a small space in between, but I think it looks nicer if you work your way around with the Kit Kats pressed closely together.
  • When the Kit Kats are completely attached to the sides of the cake, open the M&M’s and pour over the top of the cake. There should be enough Kit Kat overhang (did I really just type that?) to hold the two large bags of M&M’s. You shouldn’t see any frosting, just Kit Kats and M&M’s!
  • Finish the cake by tying a pretty bow around the Kit Kats. Decorate the top with decorative candles. This cake will keep for about a week if its not immediately devoured (which, let’s face it, it will be).



I still had the last layer of cake to deal with, so I quickly masked it in leftover frosting and smashed the leftover Kit Kats in a plastic bag with a wine bottle (that’s technically the correct way to smash things). I sprinkled the smashed Kit Kats over the top and Pat and I had dessert for a week! Not that we needed it.


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