Preheat the oven to 210°C.
Cut the butter into small pieces. Place the water, sugar, salt and butter in a saucepan and bring to the boil. Once boiling, remove from the heat and mix in the sifted flour. Return to the heat and mix until the mixture no longer sticks to the bottom of the pan. Transfer into a food processor and beat in the eggs one by one. The mixture should be shiny and smooth and have a dropping consistency. You may not need to add the whole of the third egg.
Place the mixture into a piping bag and pipe small profiteroles on to a baking tray. Transfer to the oven and bake for 10 to 15 minutes.
Cut the vanilla pod in half lengthways and scrape out the seeds. Whisk the cream to soft peaks and sieve the icing sugar and vanilla in. Fill a piping bag with this mixture.
Make a small hole at the bottom of the profiterole and fill with the chantilly cream.
Place the double cream in a saucepan and bring to the boil. Break the chocolate into small pieces and then pour the cream over the top. Whisk until the chocolate has melted and you have a smooth and shiny sauce.
Dip the top of the profiteroles into the chocolate sauce and leave to cool.
«Try flavouring the cream with orange zest, chopped up hazlenuts or even espresso coffee.»