This giant tim tam recipe would make an excellent option for a Birthday cake alternative idea. The tim tam bar is very similar to a penguin bar in the UK and they are extremely popular! And very easy to make your own homemade ones too! But for this we are going a little larger, the tim tam slam thing is a bit optional and a bit of fun, but it’s really, really good without doing that step – my family and friends literally destroyed this thing. Chocolate biscuits, wedged with chocolate buttercream filling sealed in chocolate – what’s not to love?!
Start by lining a large baking tray with baking parchment, pre-heat an oven to 160c fan or equivalent. In a large mixing bowl mix together half of the granulated sugar and half the butter, mix this really well until smooth and fluffy either by hand or a stand mixer. Add in half the cocoa powder, the flour, a pinch of salt and 2 eggs and beat well until you form a thick dough, form it into one ball.
Flatten this into the baking tray area and fill it out evenly, levelling it as best you can. Bake in the pre-heated oven for 16-20 minutes, it will still look a little soft, but it will firm as it cools, place on a wire rack to cool to room temperature. You should also keep your eye on it while baking just in case it catches earlier.
You’ll notice I said half of the ingredients above, that is because we have only made one biscuits, when the baking tray is cooled (or unless you have two identical ones) repeat the steps above and bake / cool a second biscuit in the oven.
Meanwhile make the buttercream, beat together the icing sugar with the butter until absorbed and creamy, add in the cocoa powder and malt powder and beat again until smooth and chocolatey, don’t eat it, it will be tempting!!! Place into the fridge to help it firm up until the biscuits are cooled.
For the first biscuit melt together 100g of milk chocolate and 100g dark chocolate in the microwave in a bowl on 30 second blasts, stirring in between. Brush onto one side of the biscuit and place in the fridge (or freezer if you can) to cool and set – this will be the bottom layer. The remaining chocolate can be melted either in the microwave or over a bowl of simmering water as in the video – make sure the water does not touch the bottom of the bowl and only begin to melt the rest near to when this first chocolate top is ready.
With the chocolate layer set on the biscuit in the fridge, turn it onto a wire rack chocolate side down. Dollop the buttercream onto it and spread out evenly. Place the other biscuit half on top and press down to seal and push the buttercream only slightly out from the edges. Use a spatula to brush down the sides and make them smooth. Now carefully pour the melted chocolate onto the tim tam ensuring it covers all sides. Lift up to drop any excess chocolate so it doesn’t stick to the wire rack and place in the fridge to set – it took mine 3 Hours.
Cut up into big slice and serve, tim tam slam not recommended, but fun!