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When it comes to birthday cakes, I am used to creating sweet, icing-loaded creations in the shape of Disney characters. These requests leave me unfazed, but my father, who is a dark chocolate aficionado, asked me to bake the cake for a big birthday lunch, which will require a different level of sophistication.

I have a wicked recipe for a flourless dark chocolate cake. But without flour, a cake has little structure, so this won’t do for a celebration cake that needs enough layers to look grand and feed a crowd. Instead, I am going to make a standard chocolate cake and go wild with dark chocolate shards. The only problem is that I have never worked with chocolate before, as I have been put off by the complicated process of tempering.

Tempering chocolate involves melting and cooling it several times in order to change the composition of the crystals within. Get it right and your chocolate will be gloriously glossy, have a perfect snap to it and will melt in the mouth rather than in your hands (or on the cake).

Not only is the process laborious, but it also requires equipment (admittedly only a thermometer). Like any busy baker, the first thing I do is look for shortcuts, and it turns out that scientists are on the case.

In 2021, isolated various parts of cocoa butter and tested their effects on tempering. They found two phospholipids – minor components of cocoa butter – that are usually removed in chocolate production can be added back in to chocolate in tiny proportions to produce the type of crystalline structure normally achieved through tempering. Sadly, the researchers don’t specify how the humble home cook can achieve the same effect. Eggs are one source of phospholipid, so I consider experimenting with tiny additions of egg yolk, but decide this is more complicated than tempering itself.

Defeated, I embrace the task (and buy a thermometer). The fats in cocoa butter can take six different crystal forms, which all have their own melting point. We want to achieve the maximum amount of type V crystals, which melt at 33.8°C (92.8°F). Start by melting your dark chocolate to 45°C (113°F) in order to break down all the crystal forms. There are various ways to melt your chocolate, but, being French, my go-to is a bain-marie, or double boiler. Then, remove from the heat and gradually cool the chocolate to 27°C (80.6°F) by placing your bowl into a larger bowl of cold water and stirring. You will now have mainly type IV and V crystals. Finally, return to the bain-marie and heat again to 32°C (89.6°F) to get rid of the type IV crystals.

Your chocolate should now contain only type V, and be smooth and shiny and ready to mould. For dramatic shards, spread the molten chocolate onto acetate and, when cool, snap into irregular shapes.

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Catherine de Lange is the editor of New Scientist and an avid baker