4 tbsp golden caster sugar
1 tbsp custard powder
1 tbsp cornflour
200ml/7fl oz semi-skimmed milk
2 large egg yolks
125ml/4fl oz single cream
1 vanilla pod
140g/5oz half-fat crème fraîche
Stir 2 tbsp of the sugar, the custard powder and cornflour in a medium bowl with 2 tbsp of the milk to make a smooth paste. Beat in the egg yolks with a fork until well combined. Pour the remaining milk into a pan, preferably non-stick, then pour in the cream. Slit the vanilla pod lengthways and scrape the seeds into the milk. Drop the pod into the pan and bring the creamy milk just to the boil – as soon as you see a few bubbles rising to the surface, remove from the heat.
Slowly pour and stir the hot milk into the cornflour mix, including the vanilla pod, making sure the yolks are well blended in. Transfer to a clean pan. Cook over a low heat, stirring continuously with a wooden spoon, for about 15-20 mins until the mixture is very thick – when you drag the spoon across the bottom of the pan, it should leave a clean line (see above right). It should be much thicker after about 10 mins, but keep stirring until the mixture has thickened sufficiently to look like softly whipped cream or mayonnaise (see above right). Keep adjusting the heat so that the mixture does not come to the boil or overheat, as it may curdle and become lumpy. If this happens, beat the mixture smooth with a wire whisk.
Remove from the heat, transfer to a bowl and leave to cool for 15-20 mins, stirring occasionally to prevent a skin from forming. Remove the vanilla pod. Stir in the crème fraîche and divide the mixture between 4 small ramekins (about 125-150ml capacity each). Spread the mixtures level, then chill, uncovered, overnight. By not covering them, a thin skin can form on top of the brûlées, which will help support the caramel layer.
Before serving, spoon the remaining sugar over the top of each brûlée (allow 1½ tsp per ramekin) and smooth over with the back of the spoon. To caramelise, use a blowtorch. Hold the flame just above the sugar and keep it moving until evenly caramelised (don’t take too long or you will heat up the custard too much). If the custard looks as though it has softened slightly, put the ramekins in the fridge for 5-10 mins to firm it up again. Serve while the caramel is still brittle.