Actually it’s kind of cretaceous
This week was Professor Plum’s birthday. Those of you who remember the treat she arranged for me for my birthday a couple of months back will know how difficult that would be to top. In fact, it didn’t even seem worth trying to book a more exciting restaurant. As we’d spent a lot of time away from home recently, a nice home cooked dinner seemed a more appropriate way to celebrate. Without the pressure to deliver something on a level with Heston’s Dinner, I was able to indulge in the fun of a nostalgic childhood style birthday cake.
When I asked Professor Plum what sort of cake she would like for her birthday (meaning chocolate or lemon or coffee or something), she responded “dinosaur”. I laughed, but there was definitely something in that. Cakes in the shape of dinosaurs had certainly been something we’d enjoyed as kids and, as adults working in museums together, we always enjoy visiting the ones with dinosaurs in (in fact, on my own birthday we took advantage of being in the area for Heston’s Dinner to pop in and visit Dippy the diplodocus at the Natural History Museum).
Thinking about the idea of a dinosaur cake and the fossilised dino remains in our museum visits made me realise the potential similarity in appearance between the tiers of a layer cake and those of geological strata. Maybe, then, what we wanted wasn’t a cake in the shape of a dinosaur, but a cake with dinosaur bones in it. How, then, to make fossils fit for a cake? What should I make them with? Having progressed beyond “dinosaurs” being her leading desire, Plum expressed a further liking for chocolate cake, so it was from chocolate that these fossils needed to be made.
A little while back I came across something called chocolate plastic, which is essentially a sugar fondant substitute that you can use to mould and shape things for cake decorations. It’s incredibly simple to make, you just need to melt a 150g packet of chocolate (white is easiest because you can colour it) and then stir in 2½ tablespoons of golden syrup and, once you’ve allowed that to set in the fridge for a few hours, it can be moulded like playdough into whatever you want. When it comes out of the fridge it can be literally as solid as real plastic, but as you warm it in your hands it becomes soft and malleable and, eventually, excessively sticky. That’s the window in which you can shape it, making sure to roll it in sugar to prevent the stickiness phase coming almost immediately.
Given that my childhood image of an paleontological dig site is entirely drawn from the early scenes of Jurassic Park, I decided to have a velociraptor type dinosaur on the top of my cake. Despite the movie’s name, velociraptors are cretaceous dinosaurs, meaning the layer of the cake below the icing would be jurassic, the middle layer triassic and the bottom layer a pre-dinosaur permian era. Now, I’ve only ever used the chocolate plastic to mould roses for Valentine’s Day, so entirely accurate dinosaur skeletal remains were probably out, but I felt it was important for the fossil-layer cake concept that they be vaguely appropriate to their individual layers, with ammonites and a dimetrodon-type sail backed reptile in the bottom part of the cake, the skull of a crocodilid archosaur and the three toed foot of an early dinosaur like coelophysis in the middle layer as dinosaurs began to emerge in the late triassic, and the (not even remotely to scale) remains of larger, better known dinosaurs from the jurassic period in the top layer – a brachiosaur skull and some stegosaur plates.
For the cake itself, I decided three layers meant three different types of chocolate. The easiest way to make a cake is to weigh the eggs and then make sure all the flour, sugar and butter weigh the same, so that’s what I did with two eggs for each layer. Adding a little vanilla for flavour and milk for texture, I then put a bit of melted white chocolate in the middle layer and cocoa powder in the other two, along with a little melted dark chocolate in one and milk chocolate in the other. I buried the fossils in their respective layers and sandwiched a white chocolate ganache between each. A ganache is a simple way to cover a cake, with the most basic just being an equal amount of whipping cream and chocolate (although a white one is much harder to set, so needs a little butter as well), so I made a dark chocolate ganache and coated the whole cake in it, leaving just the top to decorate.
As I’ve already said, I wanted the top of the cake to be a paleontology dig uncovering a velociraptor type dinosaur, so I made a whole dino skeleton (or at least a skull, spine, tail, ribs and some legs) out of the remaining white chocolate plastic. Given the mix of good quality white chocolate and golden syrup gave the chocolate plastic a slightly off white colour, this was ideal for the look of dinosaur bones, however I decided while putting the dinosaur on the cake that I wanted Professor Plum herself to feature as part of the design, excavating the dinosaur herself (maybe that’s what she’s a professor of). To do that I had to make more chocolate plastic and mix it with food colourings.
Getting the chocolate to take on the right colours for the (currently) pink haired Plum was a little tricky, especially mingling pink and yellow food colouring to get something that approximated skin colour. Meanwhile, only adding a little colour just makes the chocolate mix look streaky, but adding enough to get a bold, consistent colour, as in her black shoes, gives it a slimy texture that’s hard to work with. As a result, the best I could manage was this round faced Morph-like creation that has a kind of cute cartoonishness, but does little to flatter the attractive birthday girl.
Finally, I needed to cover the dinosaur bones so that the real Professor Plum (and her choco-avatar) could uncover them. Like a mogwai, you should never let chocolate get into contact with water. If that happens then the chocolate loses its smooth texture. However, there is one situation where you need to do just that. “Chocolate soil” is chocolate crystallised by mixing with a sugar and water syrup and is pretty superfluous for most situations unless you’re looking for a topping that looks like soil and tastes like chocolate, which is exactly what I was after. Covering my dinosaur bones with the chocolate soil, I finished the cake by cordoning off the dig area using the birthday candles and then presented it to the happy birthday girl.
Overall I was pretty pleased with my first attempt to make things more complicated than flowers for cake decoration. The dinosaur bones looked pretty good and I think I can improve on chocolate people with a little more practice. Plum seemed pretty pleased with the finished result and certainly enjoyed having a go at uncovering the “fossilised” remains with a pastry brush! If we ever have kids, then this is exactly the kind of cake they’re getting.
Professor Plum in the Dining Room: So when Colonel Mustard asked me what sort of cake I wanted for my birthday, since I’d be away while he was making it, I said chocolate. And then I said dinosaur, though I don’t entirely remember why (beyond dinosaurs being awesome, of course). The I came home to a chocolate cake with a chocolate me excavating a chocolate dinosaur from chocolate soil, on top of layers of chocolate cake geology complete with chocolate fossils in the right (chocolate) geological order. Or to put it another way: Colonel Mustard is mine, and you can’t have him.