Preheat oven to 160°C (140°C fan forced). Lightly grease a 20cm round spring-form cake tin and line base with baking paper. Line a 1.5 litre capacity pudding bowl with plastic wrap, allowing extra to overhang, for covering the top.
For the chocolate cake, place pastilles in a mixing bowl over a saucepan of boiling water, off the heat, stirring occasionally until melted. Remove mixing bowl from heat and allow chocolate to cool slightly.
Meanwhile, using an electric stand mixer, beat butter and sugar together for 5 minutes or until light and fluffy. Add eggs one at a time, beating well between each addition.
Add the flour and salt to the egg mixture and using a large metal spoon gently fold into mixture. Add cooled chocolate and again fold to combine.
Pour cake mixture into prepared tin and bake in preheated oven for 45 minutes, or until a skewer comes out of the centre clean. Remove from oven and allow to cool in tin for 5 minutes, before turning onto a wire rack to cool.
For the Christmas pudding ice-cream, combine berry mix, spice, sugar, vanilla, brandy and zests together in a small saucepan over a low heat, stirring until well combined. Heat gently until sugar dissolves and fruit absorbs the brandy and becomes plump. Remove from heat and allow to cool completely.
In a large mixing bowl, combine softened ice cream, cooled fruit mixture, slivered almonds and Haigh’s chocolate, stirring until combined. Spoon mixture into prepared pudding bowl and cover with plastic wrap. Place in freezer overnight to set firm.
To assemble the baked Alaska, turn Christmas pudding ice-cream out of pudding bowl and carefully remove plastic wrap. Return to freezer until required.
For the Italian meringue, combine sugar and 200ml water together in a small saucepan over a low heat, stirring until sugar has dissolved. Increase heat to medium and bring mixture to the boil, brushing sides of pan with water, to prevent sugar crystals forming. Cook sugar syrup to 121°C (hard ball stage) on a sugar thermometer.
Meanwhile beat egg whites and cream of tartar together, using an electric mixer, until soft peaks form. With the electric mixer on high, carefully add the sugar syrup to the egg whites, very slowly, until syrup has been incorporated. Continue beating the mixture until it has cooled to room temperature.
To serve the baked Alaska, remove the domed top of the cake to create a flat base for the ice cream filling to sit on. Carefully place the ice cream dome on top of the cake and trim the base of the cake to line up with the ice cream filling.
If using a blow torch, place baked Alaska on a serving plate and using a spatula, quickly spread the meringue over the top of the ice cream. Carefully blow torch the outside of the meringue and serve immediately.
If using an oven, preheat to 240°C (220°C fan forced). Place baked Alaska on a baking tray and using a spatula, quickly spread the meringue over the top of the ice cream. Place in preheated oven for 2-3 minutes or until edges become golden. Remove from oven and carefully transfer bake Alaska to a serving platter and serve immediately.
TIP: Heat the knife before cutting the Bombe Alaska to make serving easier.