An adaptation of a recipe from the Heretics’ Heretic, Docteur de Pomiane. This is the simplest and lowest risk custard I know. You will need:
- 250mL milk (semi skimmed, or full cream if you’re feeling decadent)
- 3 large eggs
- 25g caster sugar (you may find you prefer less or more)
- 1 teaspoon plain flour, i.e. 5mL by volume, 4g by weight if you’ve got digital scales
- vanilla (in some form, see below)
I normally keep my vanilla pods in a tall jar of caster sugar. The sugar leeches out the volatile oils and becomes vanilla flavoured. Tonight I used both vanilla sugar, and scraped the seeds out of half a vanilla pod, carefully returning the carcass to the sugar jar for later. (You could also be shot of all this faffing, and just use a few drops of Vanilla Extract.)
- put the milk and the vanilla into a saucepan on a low heat
- separate the eggs and put the yolks, the sugar, and the flour into a bowl and mix vigorously with a whisk – as this happens it will get paler in colour and thicken slightly
- don’t forget to keep a watchful eye on the milk, and just as it starts to shudder, but not boil, take it off the heat
- wait for about 30 seconds so the milk cools slightly
- pour the milk, little by little, into the bowl with the egg/sugar mix, whisking all the time, until combined
- pour the mixture back into the saucepan, return to the heat, and stir continuously – you’re not trying to win the National Stirring Championships; just keep it on the move and make sure nothing catches on the bottom of the saucepan
- after about a minute or so, the mixture will thicken, so remove it from the heat, keep stirring for half a minute, and decant – caution: if you leave it in the saucepan, and you’ve got a high quality saucepan with a heavy heat retaining base, you could be in for an unpleasant surprise!
The addition of the flour serves two purposes: it contains some starch which helps to thicken the custard, and more importantly, the presence of the starch dramatically raises the temperature at which the custard will curdle. (And the fat in the egg yolk means that the flour can release its starch. See the chapter in Pomiane on sauces for more about the chemistry involved.)
Although delightful, this is not the custard I’d use for crème brûlée. (I’ll save those notes for another occasion.)
You could obviously infuse other things in the milk: half a cinnamon stick, some lemon peel, etc.
If you use about a tablespoon of flour or cornstarch, you will end up with something quite stiff, called crème patissière, which is used in various fillings.