I made a cake representing a local landmark for a friend's birthday. I couldn't find a lot online to help with acheiving the shape of this cake so I thought I would share my technique on here.
Step 1: You Will Need:
I used two 9" and one 6" round chocolate cakes. They need to be deep cakes and they need to be of firm texture. I used a Lindy Smith chocolate cake recipe; she is a cake carving expert and has many books on the topic, and recommends a firm but moist cake. She also has a madeira cake recipe. Fruit cake is not recommended as this crumbles easily.
Top tip for getting a perfectly even top on your cake - put it back in the cake tin on top of a cake board or similar so that the dome of the cake is protruding above the rim of the cake tin. Slice the dome cleanly off by using a large sharp knife and slice horizontally against the rim of the cake tin.
You will also need:
Cake board/drum at least 10" diameter
Butter cream (750g icing sugar, 375g butter)
Long sharp knife
I froze the two larger cakes, wrapped in a double layer of clingfilm followed by a layer of foil. I took them out of the freezer about 45 minutes before assembling.
Step 2: Mark Out Your Pathway
Sandwich the two larger cakes with buttercream (jam is not recommended as this can make the cakes slide). Place the smaller cake into position (without buttercream) in the centre of the top cake, and mark out your pathway with cocktail sticks. You want a gradual diagonal segment winding about a third of the way around the cake. Make sure it finishes at the very bottom.
Step 3: Carve the Cake
Take the smaller cake off and proceed to carefully carve along the shape marked out with the cocktail sticks, removing them as you go along. Take care not to cut too far down or across as you follow the path round.
Reserve the top segment that you have carved off.
Step 4: Assemble the Cake
Put the smaller cake back onto the top. Turn the reserved segment upside-down and place it alongside the smaller cake so that the thick end aligns with the vertical drop beneath. You may need to trim it slightly to fit snugly around the small cake without breaching the edge of the larger cake.
Step 5: Crumb Coat
Sandwich the top pieces onto the cake with buttercream and place on a cake drum at least 10" diameter.
Coat the whole cake with a thin layer of buttercream and refrigerate for 2 hours. You'll probably need to remove a shelf from your fridge!
Step 6: Decorate
You can now cover with more buttercream free from the danger of crumbs mixing in.
You can add other details. I used brown sugar to mark out the pathway and added flowers as well as deer, a folly and the birthday boy. You could make a path, a road or even a railway and add personal features depending on who the cake is for.