For the caramel poached pears, place the caster sugar into a non-stick pan over a low heat until the sugar melts. When the sugar is golden-brown, remove from the heat and quickly add the water. Return to the heat and stir until the lumps have dissolved. (NB: Stand at arm's length and wear an oven glove when you add thee water - the caramel may splatter.)
Bring the syrup to the boil and add the pears, stalks turned upwards. Turn down the heat and simmer for at least 10 minutes, or until the pears are tender. Then remove the pan from the heat and allow the pears to cool in the syrup.
For the tuile cups, preheat the oven to 180C/360F/Gas 4. In a bowl, beat the caster sugar, flour and egg whites together for 2-3 minutes or until a smooth paste forms.
Beat in the melted butter until well combined, then cover and chill in the fridge for 15-20 minutes.
Dot four teaspoons of the chilled tuile mixture at even intervals onto a lightly greased non-stick baking tray.
Spread teaspoons of tuile mixture into thin circles approximately 12.5cm/5in in diameter using a wet palette knife. Bake for 6-8 minutes, or until pale golden-brown in the centre and dark golden-brown at the edges.
Remove from the oven and set aside to cool for a few seconds. Then, using a palette knife, quickly lift each tuile biscuit off the baking sheet and shape it over an upturned cup.
Remove the pears from the poaching liquid and set aside. Bring the poaching liquid, to a simmer and reduce until it forms a thick syrup. Set aside to cool.
For the chocolate sauce, in a pan heat the water, chocolate, butter and double cream, stirring occasionally until the mixture is smooth and the chocolate has melted.
To serve, place one of the poached pears onto each of six serving plates. Fill a tuile basket with a teaspoon of crème fraîche and place it alongside the poached pear. Drizzle over the chocolate sauce.