Holiday Tradition, in Chocolate

Three years ago, I watched Nigella Lawson make a Chocolate Cherry Trifle on Food Network. It looked incredible, and I don't really like cherries that much. I decided to make it. I'm not going to post the ingredients here, you can go to the link above and find them. I am going to talk about custard making, though.

I'd made several custard-style ice creams and after watching Nigella discovered that I was doing it wrong. You should never let a custard boil.

Below, I am mixing the *8* egg yolks, sugar, and cocoa:
I didn't know that you shouldn't ever let custard boil. Oops. It will separate and you will get scrambled egg yolk in with whatever you're making. While it won't kill you, it isn't pleasant either visually or texturally.

After you mix the yolks, sugar, and cocoa in a bowl, heat the milk and cream. I heated until it was steaming:
Whisk the warm milk into the yolk mixture. Pour a little in at first, whisking like a fool, and then whisk the rest in. At this point you also mix in the melted bittersweet chocolate:
Put everything back in the dutch oven and heat over medium, stirring constantly. Use a spoon - don't us a whisk, it will just keep it frothy on top and you won't be able to see the Evil Bubbles of Boiling.

Directions always tell you to cook the custard until it is thick enough to coat the back of a wooden spoon. I have never found this helpful, doesn't it always coat the back of a spoon, just more thinly at times? Here the spoon is coated, but the custard just isn't thick enough:

She is right in her directions, too: you want this to be thick. Runny won't do. I think this time I finally found the right method for telling 'doneness.' When it is thick enough that when you push it to one side of the pan AND IT TENDS TO STAY THERE, it is done:
The recipe calls for two chocolate pound cakes, too. I used box mix with 1/3 cup of cocoa mixed into the dry mix. I know, I know, but it is easier. Also, it turns out I only needed one, so the other is currently in the freezer:
The mostly-finished product! Notice the liquid at the bottom of the bowls? Homemade cherry liquor. All it needs is freshly whipped cream *unsweetened* on top:
Even if you don't make the whole trifle, the custard part of this recipe is to die for. Really. And if I don't make this for Christmas every year my husband will kill me in my sleep, so be warned. If you make this dessert, you may be destined to make it forever.