Preheat oven to 160°C. Grease and line two 20cm (base measurement) round cake pans with baking paper. Combine the chocolate and 2 cups (500ml) water in a medium saucepan over low heat. Cook, stirring, for 5 mins or until chocolate melts and mixture is smooth. Set aside to cool.
Use an electric mixer to beat the butter and sugar until pale and creamy. Add the eggs, 1 at a time, beating well after each addition. Combine the flour, almond meal and cocoa in a bowl. Add the flour mixture and the chocolate mixture, in alternating batches, to the butter mixture, stirring with a wooden spoon until just combined. Divide evenly between the prepared pans. Bake for 1¼ hours or until a skewer inserted into the centres comes out clean. Set aside for 15 mins to cool before turning out onto a wire rack to cool completely.
Meanwhile, to make the caramel sauce, place the sugar in a saucepan over medium heat. Cook, stirring with a wooden spoon, for 5-7 mins or until sugar dissolves. Remove from heat. Slowly pour in the cream. Return to heat and cook, stirring, for 5 mins or until the sauce boils and thickens. Set aside to cool completely.
To make the whipped chocolate ganache, combine the chocolate and cream in a heatproof bowl over a saucepan of simmering water. Cook, stirring, until chocolate melts and mixture is smooth. Cover with plastic wrap and place in the fridge for 1 hour or until firm. Beat until smooth and creamy.
Use an electric mixer to beat the double cream and thickened cream until firm peaks form. Gently fold in 1/4-cup of the caramel sauce to create a marbled effect.
Use a large serrated knife to split each cake in half horizontally. Place 1 layer of cake on a serving plate. Spoon over one-third of the cream mixture. Repeat with the remaining cake and cream mixture, finishing with a layer of cake. Spread the top of the cake with the ganache. Decorate with the Snickers pieces and peanuts. Drizzle with the remaining caramel sauce.