Preheat the oven to 210°C.
Cut the butter into small pieces.
Place the water, 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 to 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 balls on to a baking tray. Bake in the oven for 10-15 minutes.
Split the vanilla pod and grate. Boil the milk with the vanilla pod and passion fruit puree.
Separate the eggs and place the yolks into a bowl with the sugar. Whisk energetically for one minute before adding the flour. Next, add the hot milk, mix again and then return to the pan. Bring back to the boil and cook for 3 minutes whisking continuously.
Transfer the crème pâtissière onto a tray, cover with cling film to prevent it from drying and set aside in the fridge.
Once the crème pâtissière is cool, whisk the double cream until it has the texture of chantilly cream and then fold into the cold crème pâtissière. Fill a piping bag with this mixture.
Pierce a small hole in the base of each profiterole and fill with the crème pâtissière.
Place the double cream and the milk in a saucepan and bring to the boil. Break the chocolate into small pieces and then pour the cream and milk mixture over the top. Whisk until the chocolate has melted and you have a smooth and shiny sauce.
Dip the top side of the profiterole into the chocolate sauce and leave to cool.
«To make eclairs use the same choux pastry mix and pipe 5cm lengths instead of balls.»