Method

• 1.
  For the mudcake, preheat the oven to 160°C fan-forced. Grease five 18 cm single layer round cake tins and line the base of each with baking paper. Combine the butter, dark chocolate, hot water, cocoa, coffee and vanilla in a medium saucepan. Heat over low heat, whisking constantly, until smooth and well combined. Remove from the heat and set aside until the mixture is lukewarm. Using a hand-held mixer or a stand mixer fitted with the whisk attachment, whisk the sugar and eggs on high speed for 2 minutes, or until pale and creamy. Whisk in the chocolate mixture until well combined. Add the flour and whisk again. Divide the mixture equally between the cake tins and bake for 20–25 minutes (rotating the tins halfway through baking if needed), or until a wooden skewer inserted into the centre of each cake comes out almost clean. (The centre of your mudcakes will still be quite sticky, almost gooey, but will come together once cooled.) Remove the cakes from the oven and allow to cool completely in the tins. Once cooled, remove the cakes from the tins, cover and set aside until it’s time to assemble the cake.
• 2.
  For the chocolate baubles, you will need a food safe paint brush and food grade silicone moulds to shape the baubles. put the chocolate in a clean, dry, heatproof bowl over a saucepan of just-simmering water (the water should not touch the base of the bowl). Gently stir with a silicone spatula until melted. (If using couverture chocolate, temper the chocolate as per the manufacturer’s instructions.) Place 4 tablespoons of the melted white chocolate in a small bowl, and another 4 tablespoons in another small bowl. Colour these as desired (I used pink and green). Use a food-safe paint brush to create decorative strokes with the coloured chocolate on the inside of each cavity of the moulds (you can use the photos as a guide), then leave to set. Fill the moulds completely with the remaining melted chocolate. Firmly tap the mould on your bench to release any air bubbles. Use the cake scraper to scrape across the top of the mould to remove any excess chocolate. Allow the chocolate to thicken slightly (around 5–10 minutes). Lay a sheet of baking paper on the bench then turn the mould upside-down and let the chocolate mix run back out onto the baking paper. Tap the side of the mould to assist the process. Once the chocolate has finished dripping out, scrape again before turning the mould back up the right way. You should have a nice, smooth layer of chocolate in your moulds. (The excess chocolate on the baking paper can be re-used at another date but should be kept airtight and at room temperature until required.) Turn the mould back upside-down and place it face down with some force on a tray lined with baking paper to encourage the chocolate to pool downwards – this will create a thicker rim around the inner edge of the semispheres. Set the semispheres by placing the moulds in the refrigerator for 30 minutes or the freezer for 15 minutes or leave at room temperature overnight. Mix the fondant with the Tylose powder. Model the fondant with your fingers and the wooden skewer to form at least five hanging tips for your baubles. Put aside to dry completely, around 20 minutes, then decorate with edible gold paint or lustre. Once the spheres have set, gently remove them from the moulds. Place both halves of each sphere on a warm frying pan or warm oven tray for 1 second only – any longer and your spheres will melt too far and lose their shape! Fill one half with candies and then carefully press both halves together and hold until completely set. Repeat this process with the remaining halves. Decorate your chocolate baubles with splashes of edible gold paint. Once dry, adhere the hanging tips of your baubles to the finished chocolate spheres with a small amount of melted chocolate.
• 3.
  As a tip, to melt chocolate in the microwave, place the chocolate in a clean, dry, microwave-safe bowl and microwave at 50% power, stirring at 30-second intervals with a silicone spatula until melted. Use a food-safe brush to paint decorative strokes of coloured melted chocolate on the inside of each cavity and allow to set. Once dry, fill the moulds completely with white chocolate. Scrape the mould to remove excess chocolate, then turn it upside-down on a sheet of baking paper to let the chocolate run out. When the chocolate has finished dripping out, scrape again. You should have a smooth layer of chocolate in your moulds. Make at least five fondant hanging tips for your baubles. Once dry, decorate with edible gold paint or lustre. Place both halves of each sphere on a warm frying pan or warm oven tray for 1 second only – any longer and your spheres will melt too far! Fill one half of each sphere with candies and then carefully press both halves together and hold until completely set. Repeat this process with the remaining halves. Decorate the chocolate baubles with splashes of edible gold paint. Once dry, stick the hanging tips onto the baubles with a small amount of melted chocolate.
• 4.
  For the buttercream, place the sugar and egg whites in a heatproof glass bowl. Set the bowl over a saucepan of gently simmering water, and whisk until the sugar has dissolved and the egg whites are slightly warm to the touch (at least 40°C). (You can omit this step entirely if you are using pasteurised egg whites, and instead, simply place the sugar and egg whites directly into the mixer.) Transfer the mixture into the bowl of a stand mixer fitted with the whisk attachment. Whisk on high speed until the mixture has formed stiff and glossy peaks, around 10–15 minutes. Switch to the paddle attachment. Add the butter in thirds, and beat on high speed after each addition until incorporated. Don’t be alarmed if the buttercream appears curdled – it will become light and fluffy again with continued beating for around 2–3 minutes (I absolutely promise!). Add the vanilla bean paste and beat until just combined. The buttercream is now ready to be used. Follow individual recipes for instructions on how to tint and flavour further. If you are making buttercream ahead of time and you find there are bubbles visible when you come to use it, you may need to mix it further before use. Using a stand mixer fitted with the paddle attachment, beat on low speed for 2–3 minutes to eliminate the air bubbles. Place three-quarters of the Perfect Swiss Meringue Buttercream mixture in a separate bowl and set aside at room temperature in a cool environment until needed. Divide the remaining buttercream evenly between two bowls and colour each portion with your choice of gel paste food colour. Cover the bowls with plastic wrap and set aside.
• 5.
  To assemble, you’ll need a food safe paint brush and a cake scraper. Working on a cake turntable, secure the bottom layer of cake onto a cake board with a small dollop of the white Swiss meringue buttercream and then gently press in place. Use an offset spatula to spread a 5 mm (¼ inch) layer of white Swiss meringue buttercream right to the edge of the cake. Repeat this process until you have used all the cake layers, leaving the final top layer uncovered. Use an offset spatula to gently crumbcoat the cake with a thin layer of white Swiss meringue buttercream and set aside in the refrigerator for 10–20 minutes, or until firm. Apply generous amounts of the two different coloured Swiss meringue buttercreams all over the outside of your cake. Now, using a cake scraper, carefully blend and smooth the side and top of your cake to achieve a watercolour look. Place your cake in the refrigerator for at least 30 minutes to firm and cool. Make the white chocolate ganache (see opposite page) then, using a metal spoon, apply the ganache drips to your cake one drip at a time, working 5 cm (2 inches) from the edge of the cake and gently working the ganache over the side. If your ganache is too thick, simply heat it in the microwave for 10 seconds. Fill the top of your cake with ganache until completely covered. To prevent the ganache drips from cascading any further, place the cake in the refrigerator again for at least 30 minutes. Adorn the cake with an arrangement of your chocolate baubles. Finally, using a food-safe paint brush, flick gold paint decoratively over the cake (if desired). Set your finished cake aside in a cool environment until you’re ready to serve it.
• 6.
  For the ganache, place the white chocolate in a heatproof bowl. In a separate heatproof bowl, microwave the cream for 30–40 seconds or until it just starts to boil. Pour the hot cream over the white chocolate, making sure that most of the white chocolate is covered. Let it sit for 5 minutes, then stir gently until the white chocolate has melted completely and the mixture is smooth. If needed, microwave for another 10 seconds at a time, stirring gently at intervals, until smooth. Colour with the whitening gel until the desired colour is achieved. Set aside until the ganache cools and thickens. It should be thick enough so that it falls in a slow stream from a spoon. If needed, chill it in the refrigerator briefly, about 5–10 minutes, and then stir again until smooth.
• 7.
  For storage, this cake will last refrigerated for up to 5 days. If refrigerated, take out at least 1 hour before serving. Store chocolate spheres in an airtight container, in a cool, dark and dry environment. For the buttercream, cover the bowl with plastic wrap and set aside in a cool, dry place until needed. You can refrigerate this buttercream for up to 10 days or freeze for up to 2 months. Thaw frozen buttercream overnight in the refrigerator, then bring to room temperature (gently reheat in the microwave in 20-second bursts if needed). Beat the buttercream on low speed until smooth before applying to your cake.