To make your eggs gleam, you need to temper the chocolate so the cocoa butter in the chocolate forms tiny crystals. The easiest way to do this at home is called ‘seeding’ and the smallest amount of chocolate that you can successfully temper in this way is about 300g. If you don’t need that much, you can store the remainder in a cool place until needed. You will need a sugar thermometer. To temper 300g chocolate, first roughly break up or chop 200g of it and grate the remaining 100g. For other quantities of chocolate simply use the same proportions.
Place the roughly chopped chocolate in a heatproof bowl set over a pan of gently simmering water until melted, making sure that the bottom of the bowl is not in contact with the hot water.
Use the sugar thermometer to check the temperature of the chocolate. When it has reached 45˚C, remove from the heat and stir in the 100g grated chocolate.
Keep stirring until the temperature of the mixture drops to 28˚C for dark chocolate, or 26˚C for milk or white chocolate.
Set the bowl over the pan of gently simmering water again and heat to 30-32˚C for dark chocolate, or 28-29˚C for milk or white chocolate. The chocolate is now tempered and ready to use.
To prepare the moulds: It is easiest making eggs when you are using single egg moulds, not ones that come with many moulds in one sheet.
Make sure the inside of your moulds are totally clean and dry. Then for complete perfection, brush the inside of them with a very thin coating of melted cocoa butter.
To make the eggs: Fill the mould with chocolate up to the top, wait until you can see 4-5 mm of chocolate set on the outside, then tip out the liquid chocolate until you have achieved an even thickness on the edge.
Then move a sharp knife over the flat top of the egg to achieve a nice edge. Place somewhere cool for about an hour, preferably not the fridge because if left there too long it will crack.
When it has finished setting, the egg should fall away from the mould when you give it a gentle tap. If you take it out too early this can spoil the shine and leave marks on the egg.