You can overcook the fish, burn the roast, under-cook the potatoes, but serve this sauce with the dessert and all will be forgiven. There are no shortcuts this time, and you cannot substitute vanilla essence for the real thing and hope to get away with it. There is just one compromise you can make.
In a restaurant we would scrape the seeds out of the vanilla pod (hugely expensive) for the sauce and use the pod to flavor sugar. You can use the pod whole, then rinse it and dry it for re-use. It will keep its flavor for weeks.
Ingredients
6 egg yolks
100g (4oz) caster (superfine) sugar
250mls (1 cup) double (heavy) cream
250mls (1 cup) milk
1 vanilla pod
Whisk the sugar into the yolks until they are white and foaming. Bring the milk and cream to just under the boil and pour over the eggs while whisking. This is important. If the milk is boiling your eggs will curdle, especially if you are not whisking them.
Now pour this mixture into a thick, small pan and add the vanilla pod. Cook over a medium heat while stirring, until the mixture coats the back of a spoon. If you want it thicker, cook for a little longer but under no circumstances add a thickening agent such as arrowroot or cornstarch.
Allow to cool and remove the vanilla pod which can be treated as above. Chill the sauce for around 30 minutes before using. Made to the consistency given, this sauce will hold its shape when spooned onto a plate, which is just what you need for a great presentation.
The sauce keeps for about 3 days in a sealed container in the fridge.
