Pre-heat oven 150°C/130 Fan/Gas 2. Put four x 150ml ramekins in the oven to warm.
To make the caramel, pour the 125g sugar and four tablespoons of water into a saucepan.
Dissolve the sugar slowly over a low heat, stirring with a wooden spoon. When there are no sugar granules left, stop stirring and boil until the sugar turns a dark copper colour.
Remove from the heat and quickly pour the caramel into the warmed ramekins. Set aside to cool and become hard.
Now, grease the ramekins above the level of the caramel. Whisk the eggs, vanilla extract and remaining caster sugar together in a bowl.
Pour the milk into a saucepan and gently heat over a low heat until just hot. Now pour onto the egg mixture. Whisk together until smooth, then pour into the prepared ramekins.
Stand the ramekins in a roasting tin and fill the tin half-way with boiling water.
Cook in the oven for about 20-30 minutes or until the custard has just set.
Remove the ramekins from the oven and onto a cooling rack. When cool, transfer to the fridge and chill overnight.
To serve, loosen the sides of the custard by tipping the ramekin and loosen with a small palette knife round the edges. Place a serving dish on top of the ramekin and turn upside down. Serve with single cream.
When making the caramel, make sure the sugar has completely dissolved before beginning to boil.
