It's a pretty basic custard - the recipe calls for cream, which we didn't have so we just used a little extra milk. This is passable, but the cream does add a richness that is desirable and I think worth the extra ingredient. Up to you - but I reckon for Christmas day you should go all out. ;-)
I prefer to use a whisk when tempering the eggs - it's just once it's back in the saucepan, and you're constantly stirring to stop it burning that I prefer a wooden spoon. The spoon does a better job of scraping the bottom of the pan and also keeps you more in touch with the thickness - the bigger surface area means it's pretty obvious when it starts to thicken up.
Up until this point, the custard is just custard - not that there's anything wrong with smooth, homemade vanilla custard - but I wanted to step it up a notch. Feel free to stop at this point if you prefer (I have to admit it looked nicer before I spiced it up) - or add a splash of rum, and a dash of cinnamon and nutmeg to make your custard all Christmassy and delicious. I was a bit heavy handed with the cinnamon - it was good hot but once cooled it took over the custard completely - so I've adjusted the quantities in the recipe down from what I used.
As an aside, we've discovered that the microwave does a pretty respectable job of steaming Christmas pudding - not quite as good as the real thing but when the trade off is between two minutes and two hours, well, it's a fairly palatable compromise. Especially when you happen to have a bit of pudding mixture left in the fridge from making the Christmas ones up way in advance. Keep a close eye on them, though - they can go a bit tough around the edges if you cook them for too long, and cooking time will vary a fair bit depending on your microwave, how big they are and what sort of dish you cook them in.
I poured the custard straight into the ramekins, on top of our microwaved pudding - ready to eat! (see what I mean about the froth, though? It's pretty fluffy)
Would you go easy on the cream to make it lighter on the hips (or because you don't have any!) or are you all about the full flavour option?
1 tsp vanilla extract or vanilla bean paste
4 egg yolks
30g castor sugar
2 tsp/5g cornflour
1/2 tsp cinnamon (optional)
1/4 tsp nutmeg (optional)
2 tsp rum (optional)
Bring milk, cream and vanilla to simmering point slowly over a low heat.
Whisk yolks, sugar and cornflour together until well blended. Slowly pour milk mixture onto egg mixture, whisking all the time. Return to the pan over low heat, and stir continuously until it thickens to coat the back of a spoon. If using, add cinnamon, nutmeg and rum. Stir to combine. Serve hot or chill and serve cold.