Pre-heat your oven to 160C fan/Gas Mark 4, grease and line a 12" x 9" traybake tin
To make the genoise sponge whisk the eggs with the golden caster sugar in a stand mixer for about 7 minutes until thick and trebled in size
Sieve in the plain flour and the cinnamon in three stages, and gently fold them in each time. Add the melted butter by pouring it around the edge of the bowl and folding it in. Pour the batter into the lined tin
Bake it for 25 minutes until risen, golden and a skewer inserted comes out clean. Let it cool then wrap it up and put it in the freezer for an hour
To make the apple filling heat up the chopped cooking apple with the cinnamon and the light brown sugar on a low heat for 15 minutes until the apples are soft. Let the mixture cool, then whizz it up using a hand blender
Take the cake out of the freezer and brush the top with apricot jam
If you are using white fondant, knead some orange food colouring into it first until you get the desired shade. Roll out the fondant and cover the cake with it
Trim the edges of the cake then using a ruler cut it into 1.5" squares. Then cut each square into half horizontally
Spread the apple filling onto the bottom half of the cake and sandwich them all back together
Make a caramel buttercream by mixing the butter, golden icing sugar and caramel extract together. Use a palette knife to coat the sides of each cake with the buttercream, then put them in the fridge for an hour for the buttercream to set
Make a pourable fondant by mixing up the ready to roll fondant with the water. Set up a cooling rack with a baking tray underneath and using it to place the cakes on before the pouring the fondant over the top
Pour the fondant over the top of the cakes and encourage it around the sides to fully cover each cake
Melt the white chocolate, put it into a piping bag and piped a zig zag pattern on top. Add some bronze sprinkles if you wish, or any decoration of your choice, then leave the fondant to set
Serve once the fondant has set and eat leftovers within 2 days