450g raspberries
1 vanilla pod
584ml carton double cream
6 large egg yolks
50g golden caster sugar

1. Tip all but 6 of the raspberries into a sieve set over a bowl, and press them through using a wooden spoon (discard the seeds left in the sieve). Skim off any foam from the raspberry puree, cover and chill in the fridge together with the remaining raspberries.

2. Split open the vanilla pod and scrape the seeds out into a pan. Add the cream and the vanilla pod and slowly bring to the boil. Meanwhile, tip the egg yolks and caster sugar into a bowl and whisk until pale and creamy. Once the cream has reached boiling point, pour it over the egg mix, stirring all the time. Pour this mixture back into the pan, put it over a very low heat and stir with a wooden spoon for 2-3 minutes until it begins to thicken - don't let it get too hot, or it may curdle. 

3. Remove the pan from the heat and stir the custard for a couple more minutes. Strain into a bowl, cover with cling film and leave to cool, then swirl in the raspberry puree. Spoon into 6 glasses or bowls. Cover with cling film and chill until ready to serve. Top with the chilled raspberries just before serving.