Tim Tam Cake

Hiya! After all the pretty Easter treats I shared with you last week, I'm now giving you a lumpy brown cake. But this is no ordinary chocolate cake. Does it look familiar to you? It is my homage to my favourite Arnott's biscuit, the ever-awesome Tim Tam. If you've never had a Tim Tam from Australia, you're missing out. If you don't like Tim Tams, I'm sorry but we can't be friends. These biscuits are one of the few chocolate treats that I am powerless to resist, I can eat an entire packet of Tim Tams in one sitting. (Which is why I hardly ever buy them anymore. I ate half a packet while I was making this cake!)

So as I was saying, this is no ordinary chocolate cake. It is a Tim Tam cake. It looks like a giant Tim Tam AND it has a pack of Tim Tams hidden inside it. Insanity. Also delicious. And easy!! Ever since I made my Iced Vovo Cake for Australia Day, I've had demands for all kinds of other Arnott's inspired cakes. I decided to save my Tim Tam cake attempt for Tomred's birthday (Happy Birthday for Saturday Tomred!), and I am quite surprised by the results. The idea was simple enough, chocolate cake with a butter icing filling and chocolate ganache drizzled on top, but I was super worried the cake would just be far too rich and heavy. So I decided to use a very light and fluffy chocolate sponge recipe for the cake, which made it more like the light chocolate biscuits you find in a Tim Tam. It worked perfectly, and made the cake soooo much lighter and less rich than my usual chocolate cake recipe. The thin layer of gooey chocolate ganache, and the slightly denser chocolate icing in the middle give this cake a whole range of different textures. It really surprised me how much easier this cake was to eat just because of the lighter sponge.

Now I realise my outer layer of chocolate is a bit darker than an original Tim Tam, so it looks more like a dark Tim Tam. I couldn't help it, I didn't buy enough milk chocolate! But the ganache worked great, as it started to thicken up I spread it all over the top of the cake and used a spatula to create the little ripples in the surface that you always see on a Tim Tam. Definitely not going to win any awards for being pretty or delicate, but it will make any Tim Tam lover (or chocolate lover) extremely happy. I didn't realise the biscuits in Tim Tam are actually malted, or I would have added some Milo or malted milk powder to the cake mixture too! Feel free to do it. Anywhoo I'm so excited to be having this super long weekend off to do absolutely nothing as I am completely sleep deprived, I hope everyone has a happy and safe Easter and Anzac Day. Oh and it seemed like good timing to be to making this cake for Anzac Day too! I dare someone to make this and do a giant Tim Tam slam.

Tim Tam Cake
(Chocolate sponge recipe from Gourmet Traveller, serves 10)
NOTE: To beginner bakers, if you are unfamiliar with sponge recipes you might want to read up on some tips on how to make a successful sponge cake before starting. Gourmet Traveller has a great article. If you prefer a higher cake to icing ratio, double the quantities below for the cake batter. You can also substitute the cake recipe for any light chocolate cake that you are more comfortable making.
4 large eggs
110g (½ cup) caster (superfine) sugar
65g cornflour (cornstarch)
35g (¼ cup) Good quality cocoa powder
1 tbsp plain flour
1 tsp cream of tartar
½ tsp bicarbonate of soda
50g unsalted butter, melted and cooled

For the cake filling:
100g butter, removed from the fridge 30 minutes before starting
150g chocolate, melted (I used semi-sweet, you can also use milk)
3 cups icing sugar, sifted
1 tbsp milk
Optional: 1 packet of Tim Tam biscuits, crushed
(If you wanted to mix things up a bit so it's not just all chocolate, you could mix a cup of raspberries into this icing, or maybe use mint chocolate instead?)

For the chocolate ganache topping:
300ml pouring cream (min. 35% milk fat pure cream)
400g milk chocolate (I only had 200g milk so I had to use some dark, which is why my ganache is a bit darker than I would prefer for a tim tam)

Line two 17x27cm rectangular slice/brownie tins, or one larger sheet cake tin with non-stick baking paper. (I actually only had one small tin, so I split all the ingredients in half and baked two separate cakes one after the other and it worked great!) Preheat oven to 180°C (350°F). Whisk eggs and sugar in an electric mixer until thick and pale (5-6 minutes, go nuts and don't underwhip). Sift over cornflour, cocoa, flour, cream of tartar and bicarb soda, fold in with spatula. Fold in butter, spoon into prepared tin. Bake in centre of oven until the centre of the cake springs back when lightly pressed (10-12 minutes). Turn onto baking paper covered wire rack and cool completely. (If you baked one large cake, cut into two equal sized rectangular cakes)

To prepare chocolate icing filling, beat butter light and fluffy and then gradually add sifted icing sugar and beat until smooth and pale. Add melted chocolate and milk and beat until smooth. (You can adjust the amount of milk you add to get the icing to the texture you want) Spread icing over the top of one of the cakes (Note: you don't need to use all of it, I made it about 1-2cm thick), and leave space to (if you want) place tim tams along the centre of the icing. (I saw a great tip from someone who made it, that it's even better if you crush up the tim tams before you put them in the middle to make it a lot easier to cut the cake later.) Sandwich other cake on top of the icing and biscuits. To prepare the chocolate ganache topping, break up chocolate into small pieces and place in a large mixing bowl. Slowly heat cream in a small saucepan. Just as it starts to come to the boil, remove from the heat and cool for a couple minutes. Pour hot cream over chocolate and set aside 10 minutes to allow chocolate to melt. Mix cream and chocolate together until smooth using a whisk, then cool (I placed mine in the fridge for about 15 mins) until it reaches room temperature and thickens. Pour over the top of the cake, using a spatula to ensure the ganache covers all the top and sides of the cake (the excess will drip off everywhere so make sure you lay down some baking paper to catch the drips). Chill in the fridge until the ganache sets, then peel off the bottom baking paper and serve cake at room temperature. P.S. I used a big cookie cutter to cut out a 'bite' of the cake, which I really liked the look of. The cake looks less Tim Tam-like when it's whole!

Edit: You can also see a version of this idea in Australian Good Taste Magazine, it has an easier chocolate cake recipe and they've called it a 'Timtastic Cake'. What a co-inky-dink. (And also on Taste.com.au as a Tim Tam Cake)