Friday, 1 June 2012
I'm not sure I can imagine a life without custard. It seeps into so many recipes and cultures. It never stops flowing into trifles and over crumbles.
As well as creating custard to pour lavishly over your dessert, this method (and variations upon it) can be used to make a stirred custard base for ice cream. And that's before we even look at baked custards like crème brûlée, custard tarts, crème pâtissière style concoctions or relatives like lemon curd.
Yet traditional custard can be a bit daunting - all the talk of curdling, lumps and long stirring times often put people off (and, it seems, a rather strong attachment in the UK to custard powder). Being able to make an egg-thickened custard is a great skill to have, which is why I chose it for this series.
Though you can use vanilla extract as flavouring, there's nothing quite like infusing custards with a proper vanilla pod. Above I've shown my method for splitting and scraping a pod. The photos run l-r, top to bottom.
1/ Take your pod and place it on a chopping board. Hold it down then run your knife along the pod at an angle to flatten it - it may be easier to use the blunt side of your knife.
2/ Insert your knife into the middle of the pod, then pull down along it, splitting it. It can help to press lightly on top of the knife with a finger as it moves.
3/ Run the knife down the inside of each side, removing the seeds.
4/ Add both the seeds and the scraped pod to the pan.
When you want to start making your custard, you need to get everything ready.
For my custard (based on this recipe) I had 300ml milk, 1 vanilla pod, 5 egg yolks, 25g caster sugar and 50ml double cream.
In particular, your yolks need to be in a bowl by the stove (as you can see, I'd run out so a big teacup had to do) with a whisk handy (the first one I tried was too big for my teacup, so do check). It's also helpful to have the cream in a jug big enough to hold all the custard (i.e. not the one pictured...) and to have a sieve on hand.
Add the milk and sugar to the pan with the vanilla pod. Place over a medium-high heat and briefly whisk to release the seeds and help the vanilla infuse.
When it starts to steam, you're ready to temper the egg yolks. Turn the heat off.
Start by whisking the yolks to break them up. Then slowly pour in about 1/3 of the hot milk, constantly whisking the yolks.
Once you've added the 1/3 milk, quickly give the yolk mixture an extra whisk.
Return the yolk mixture to the pan, whisking as you add it. Scrape all the last drops into the pan with a spatula.
Remove the whisk from the pan and exchange it for a wooden spoon (I find a spatula doesn't hold the coating like a spoon, making it hard to test). Turn the heat back on under the pan - a low to medium heat should be enough. I would start low and then increase another time if you're happy - it will take a bit longer but is worth it if you're nervous.
Stir constantly over the heat until the custard thickens, making sure you scrape the corners and bottom to stop lumps forming. When you remove the spoon at first, the custard won't coat the back at all (see below, left).
Once it's thick enough, it will coat the back of the spoon and you will be able to draw a clearly visible line through it, as you can see on the right. (It's not normally blotchy - they seemed to have formed around clumps of vanilla seeds - but it's the thickness you're looking for).
When you're happy with the thickness, strain the custard into the jug containing the cream and stir well. You need to strain the custard to catch the chalaza (the little connecting threads between the yolk and white) and any little lumps that have formed.
The process of straining and the cold cream will also quickly stop the cooking. You can also sit the jug in a bath of ice water - ice cream recipes often include this step. Cover the surface of the custard with clingfilm so a skin doesn't form.
I should note that I generally use a recipe for custard that doesn't call for the blanching the egg yolks and sugar beforehand. Many recipes do and if you're making crème pâtissière or similar, you will need to. I haven't included it above but you essentially just whisk the two together until very pale and thick before adding the milk. Be careful to start whisking the sugar in immediately - if left on top of the yolks the sugar will 'burn' them, forming lumps.
Four recipes that use this technique:
Mixed Berry Meringue with Custard
Buttered Pecan and Butterscotch Ice Cream
Mint Choc Chip Ice Cream
Rich Vanilla Ice Cream
This is the last post of my Foundations series. The first post was on rubbing in to create pastry. The second covered brown butter, followed by a third on creaming butter and sugar, a forth about icing cakes and a fifth looking at chocolate ganache.