Ensure the moulds are scrupulously clean and dry and polish the insides with a piece of kitchen paper or cloth.
Place about two thirds - 400g (14oz) chocolate into a heatproof bowl. Suspend the bowl over a pan containing some water. Heat gently stirring until the chocolate thas melted and reaches between 45/48°C (113/118°F) for milk and white chocolate and 53/55°C (127/131°F) for dark chocolate.
Cool the chocolate. Remove the bowl from the pan and wipe the bottom of the bowl dry. Add the remaining 200g (7oz) chocolate. Stir the chocolate constantly until the additional chocolate has melted and cooled down to 27/28°C (80/82°F) for milk and white chocolate, 28/29°C (82/84°F)for dark chocolate.
Return the bowl of chocolate to the pan. Continue to stir and gently reheat to 29/30°C (84-86°F) for milk and white chocolate, 31/32°C (87/89°F) for dark chocolate. The chocolate is now tempered. Remove the bowl from the heat wiping the bowl dry again
Spoon enough chocolate into the mould to fill by about a one-third then tilt the mould until the chocolate has coated all the inside of the mould. Then hold over the bowl of chocolate and tip out excess. Next, use a palette knife to remove the chocolate from the surrounds of the mould. This will neaten the edges of the shells making it easier to join the two halves of the egg together later.
Place the coated mould upside down on the work surface of a baking tray for about 5 minutes. Turn upright and allow the chocolate to set. Repeat the process of filling with more chocolate and removing the excess chocolate.
Set the chocolate shells aside and allow the chocolate to set for at least an hour, avoid putting them in the fridge. Once the chocolate has completely set it will have shrunk very slightly. loosen the edges of the chocolate buy gently pulling at the moulds. Then turn over and carefully press the chocolate shells out.
Heat a baking tray in the oven or a heavy based frying pan on the hob until hot.Gently place the matching egg shell on the hot surface for a second or two so that it melts the edge of the chocolate shell a little. At this point you can place a few additional chocolates or sweets inside one egg half before carefully joining up the two halves, holding the egg together whilst the melted chocolate starts to sets and ‘glue’ the two pieces together.
Leave the eggs plain or pipe tiny shells of royal icing along the join. Decorate as desired.