Preheat the oven to 350 degrees F. Butter the bottoms and sides of two 8-inch round cake pans and line the bottoms with parchment paper.
To make the cake: Cream the butter and sugar together in a bowl until soft and fluffy. Add the vanilla and one egg and beat the mixture like mad, then add another egg and beat it well. Add a couple of tablespoons of the flour, stir, then repeat, adding two more eggs, one by one, beating well between each addition. Add the rest of the flour and mix well to combine.
Divide the mixture between the two prepared pans, smoothing out the tops. Bake on the middle shelf for 25 to 30 minutes or until a skewer inserted in the center of the cakes comes out clean. The cake will feel springy to the touch, be golden brown and will smell cooked. Remove the cakes from the oven and immediately brush with the sugar syrup, see below. Cool completely in the pans.
Make the sugar syrup: While the cakes are cooking, put the sugar and water into a small pan over medium-low heat and stir until the sugar is dissolved. Turn up the heat and let the mixture boil for 2 minutes. Remove the pan from the heat and set aside.
Make the buttercream: While the cakes are cooling, put the butter and vanilla into a large bowl and beat well with a wooden spoon until it is light and creamy. Add the powdered sugar a little at a time, beating until the mixture is combined and becomes lighter. Set aside.
To ice the cakes: When the cakes are completely cool, remove them from the pans. To make icing them easier, put them into the freezer for 20 minutes to get them nice and hard. Put a cardboard cake round, if you have one, onto a plate. Put a small dollop of buttercream onto the round and place one of the cakes on top. Spread the cake with buttercream and place the other cake on top. Now the fun bit: spread lots of the buttercream over the sides and top of the cake; spread it quite liberally at first, then smooth it out round the edges and over the top to give a neat first layer. Put it into the refrigerator or use the freezer if you, like me, are a little impatient when it comes to cake, and let it harden. Once it is hard, remove it from the refrigerator or freezer and spread over another layer of buttercream. Try to get it smooth so the edges are really sharp. Put the cake into the refrigerator to set.
Make the graffiti: Line 2 baking sheets with parchment paper. Have a measuring cup, a cup of cold water with a spoon and a cup of cold water with a small pastry brush.
Put the sugar into a heavy-based medium pot together with the water and liquid glucose over medium heat. Swirl the mixture a little rather than stir it, otherwise the glucose can stick to the spoon. Once the sugar has dissolved, turn up the heat and let it boil away.
If there is any sugar stuck to the side of the pan, brush it off with the wet pastry brush.
The sugar needs to be cooked for 10 to 15 minutes, but check it every 5 minutes to see if it's ready. To check, take the teaspoon from the cup and dip it into the hot mixture, carefully scooping out a small amount, then put the spoon back into the cup and leave it there for a minute or so to cool down. Pick up the spoon and feel the sugar mixture on the end of the spoon. If it has disappeared, that shows the mixture is in the very early stages of cooking. Let it boil again and test using the same method; if the mixture is soft, it is still not ready. It will go through various stages until the hard crack stage: the sugar mixture will be rock hard on the end of the spoon when a bit is scooped out and plunged into water and left there for a minute or two. The mixture in the pan will also start to go a very light brownish color.
Once the mixture reaches this stage, turn off the heat and add a few drops of food coloring and vanilla. Stir as little as you can so it is just combined and then extremely carefully pour the sugar into the jug. Use oven gloves when handling the pan, as hot sugar can spit and burn you. Leave to cool for a minute or so, then drizzle a long band of graffiti squiggle shapes on the baking parchment. Use a hair dryer to keep the sugar syrup pliable if necessary. The graffiti can be as long as you like, but needs to be at least as high as your cake. Once you are satisfied you have enough bands (and it is good to have a few, as they do break), set the jug down and wait for a few moments for the sugar to harden a little.
Remove the cake from the refrigerator. When the graffiti is firm but still pliable, carefully peel off the back for the baking parchment and stick the graffiti around the cake. If you have one long piece that can go around that's great, but small pieces done patchwork style look good too. Once the sides of the cake are covered, you could arrange berries of your choice or chocolate shavings on top.