This is the pastry cream you want for things like Napoleons, layer cake filling, or other applications where the pastry cream must stand up on its own and not run. First thing, combine your milk, cream and sugar in a large saucepan, get it on the heat, and while it’s warming, slice your vanilla bean in half, slice that half in two lengthwise, then using a sharp, short knife, scrape out the seeds.
Why a short knife? Because if you use a long one you’ll end up flicking that little mound of seeds to the other side of the room. Trust me on this, short gives you much more control. Add it to the cream mixture and whisk briskly until all you see are flecks (individual seeds) floating around.
Now then, to the dry ingredients. Combine the rest of the sugar, the corn starch and the pinch of salt in a large bowl. Whisk to combine them like so.
When the milk/cream mixture is at the boil, add your egg yolks to the dry ingredients…
…and once again whisk until you’ve got a smooth, thick and pale yellow mixture.
Whenever you’re ready, pour in about 75% of the boiling cream. Don’t worry, the eggs won’t cook…
Whisk it like mad:
Once the yolk mixture has been thoroughly incorporated pour the whole mess back into the sauce pan…
…and return it to the heat. In under a minute’s time the pastry cream will thicken up nicely and give up sputtery, messy bubbles. Plorp, splorp, plop.
As soon as that starts to happen your pastry cream is done. Pour it onto a half sheet pan, cookie sheet or plate to cool. Smooth it out into about a 1/2-inch thick layer…
…cover it with plastic wrap and once it’s cooled to room temperature, put it into the fridge to chill.
Now then, there’s a big difference between a “finished” pastry cream and a “ready-to-use” pastry cream. This will firm up to a consistency not unlike leftover mashed potatoes:
but you want that kind of body for things like Napoleons and éclairs. All you need to do when you’re ready to use it is put a quantity in a bowl and stir it until it’s smooth:
What you’ll be left with is a nice, thick and pipe-able cream, infinitely superior to JELL-O vanilla pudding mix: