Serve this fabulous parcel and reveal the hidden baubles inside. It’s easier to make than it looks.
Make the coloured bauble sponge. Heat the oven to 180°C/160°C fan/Gas 4. Beat the butter and caster sugar in a stand mixer fitted with the beater until light and fluffy. Add the eggs, one at a time, beating well after each addition, then sift in both flours along with the orange zest and juice and beat on low speed until just mixed.
Divide the mixture in half, then divide one half in half again to give you three bowls of 350g, 175g and 175g. To the large bowl, add about 1 tsp of red food colouring to make a deep red batter. To one of the smaller bowls, beat in about half a teaspoon of green food colouring. To the other small bowl beat in about half a teaspoon of purple colouring. Transfer each portion into a separate large piping bag and cut a 2.5cm hole at the end.
Piping parallel to a short edge of the prepared swiss roll tin, pipe alternate strips of red and green batter halfway along the tin. Pipe alternate strips of purple and red for the other half (this will give you two bauble variations).
Take the wide end of a bamboo skewer and drag it through the mixture, about 2.5cm from the edge parallel to the longest side of the tin. Repeat this across the tin in alternate directions to feather the batter from edge to edge.
Bake for 12–15 minutes, until just firm to the touch. Leave to cool in the tin for a few minutes, then invert onto a cooling rack. Peel off the paper, then invert again onto a fresh piece of baking paper on a work surface. Use the cookie cutter to cut out about 20 bauble shapes. Set them aside to cool until ready to assemble.
Make the hazelnut sponge as in Step 1, adding the ground roasted hazelnuts with the dry ingredients. Spread about one third of the batter into the square cake tin, then arrange one row of about 10 red and green bauble shapes tightly packed together in a line like a sausage on the cake about 4cm in from one edge. Make sure the top of each bauble is tilted towards one of the top corners of the tin.
Line the red and purple bauble cakes along the other side in the same way. Carefully spoon the remaining hazelnut cake mixture all around the baubles and spread the mixture evenly. Bake the cake for about 1 hour 20 minutes, or until a skewer inserted in the centre (but not the baubles) comes out clean.
While the cake is baking, make the syrup. Heat the orange liqueur and sugar in a small pan over a low heat, stirring continuously until the sugar has dissolved. Remove the cooked cake from the oven, leave it for 2 minutes in the tin, then prick it all over with a cocktail stick and drizzle over the warm syrup. Leave the drizzled cake to cool in the tin for a further 12 minutes, then turn out onto a wire rack to cool completely. Brush a little syrup on the sides of the cake to keep it moist.
While the cake is cooling, make the ganache. Melt the butter and cream together in a medium pan over a low heat. Place the chocolate in a medium bowl, pour over the cream mixture and leave for 5 minutes, then stir until the chocolate has melted. Stir in the salt and liqueur. Allow to cool for 10 minutes, then chill until thick enough to spread.
Place the cake on the board, marking the board to indicate the front of the cake, so that you know how to slice it. Cover with a thick layer of ganache, making sure the surface is flat and even, then chill the cake for 30 minutes. Measure the dimensions of the top and sides.
To decorate, dust the work surface lightly with icing sugar. Reserve 100g of the red sugar paste and roll out the remainder to 5mm thick. Cut out the paste to fit the top and sides of the cake. Apply the side panels, then apply the top, using icing smoothers to create a smooth, flat surface. Roll the remaining red sugar paste into a rectangle about 6 x 14cm and cut it into 6 strips, each measuring 1 x 14cm. Loop the strips and place them in the centre of the cake, like a bow. Reserve the trimmings and roll them into a ball. Place this in the centre of the bow. Sprinkle with lustre powder.
Gently push the star cookie cutter into the icing to leave an indentation. Mix the lustre powder with a drop of liqueur, then paint the star shapes gold. Roll out the white sugar paste and cut out a small gift tag. Write a festive message with the icing pen and attach the tag to the cake.
To make sugar paste:
Place 5 tablespoons of cold water in a small pan and sprinkle the gelatin over. Add the glycerine and glucose and heat very, very gently, until the gelatine has dissolved. Place the mixture and half the icing sugar in the bowl of a stand mixer fitted with the beater and mix until smooth. Remove 100g, cover with cling film and set aside.
Add food colouring to the mixer bowl and gradually add about half of the remaining icing sugar to the mixer, until you have a very stiff dough. When the mixture becomes too stiff for the mixer, turn it out and knead it by hand. Add enough icing sugar to make a smooth, elastic dough, then knead in more food colouring as required. Wrap the sugar paste in cling film to prevent it drying out.
Mix the remaining icing sugar into the reserved white sugar paste, again to make a stiff dough. Wrap in cling film until ready to use.