German chocolate cake

Greetings from Toronto! I am here for a month to work on a short contract, but I have neither a kitchen or my camera, so I'm hoping to have time to share all the things I made last month and didn't get around to posting. I was actually expecting to catch up on responding to comments on the train here, but there was a problem and we had to travel by bus instead. Now, I don't romanticize the train, but it is a hell of a lot more comfortable than a bus. And it has wireless internet. And food that doesn't make you feel nasty the entire next day. Enough about that, I seem recovered now and ready for cake.

I made this for my brother's birthday. Like me, he is not a chocolate fanatic, but he does love coconut. That's what I told myself anyway, as I've been wanting to make this cake for a while. My mother used to make it for us when we were kids and I don't think I'd had it since. My plan was to use a recipe from America's Test Kitchen via Leite's Culinaria, but there were a few comments about the cake being dry, so I made one from Rose's Heavenly Cakes instead. Not only was it dark, moist and absolutely delicious, it used up a couple of extra egg whites, and I always have those around. The cake has a fairly light texture and stays soft even when cold, though our cake didn't last long enough to need refrigeration. It was huge, so if you can make yours last more than a day or two, keep it covered in the fridge and bring to room temperature to serve.
Cake
Source: Rose's Heavenly Cakes
¾ cup plus 2 tablespoons (2.3 oz/66 grams) Dutch-processed cocoa
½ cup (4 oz/118 grams) boiling water
½ cup (3.7 oz/108 grams) canola oil (I used grapeseed)
4 large eggs, separated, plus 2 egg whites, at room temperature
1 teaspoon vanilla extract
¾ cup (2.6 oz/75 grams) cake flour
⅔ cup (2.6 oz/75 grams) all-purpose flour
1½ cups (10.6 oz/300 grams) superfine sugar
2 teaspoons baking powder
1 teaspoon baking soda
¼ teaspoon salt

Preheat oven to 350℉/175℃. Grease only the bottoms of 2 9" round cake pans and line them with parchment. Cake strips are recommended for the most even cakes, but I didn't use them and it was fine. I also didn't use a stand mixer, just a hand mixer and slightly higher mixing speeds than those noted below.

1. In a large mixing bowl, whisk the cocoa and boiling water until smooth. Cover with plastic wrap and cool to room temperature. Add the oil and the yolks to the bowl. Start on low speed, then beat on medium for about 1 minute, or until mixture is shiny and looks like buttercream. Scrape down the sides of the bowl. Add vanilla and beat briefly. 
2. Whisk the dry ingredients together (including the sugar), then sift half the mixture over the cocoa mixture. Beat on low speed until moistened. Scrape down the sides of the bowl and repeat with the remaining dry ingredients. Raise the mixer speed to medium-high and beat for 1 minute. The mixture will be very thick. On low speed, add the egg whites. Gradually raise the speed to medium-high and beat for 2 minutes. The batter will be like thick soup. Divide the batter evenly between the pans (17.5 oz/495 grams) in each.
3. Bake for 25 to 35 minutes, or until a wooden skewer comes out clean, and the cakes spring back when pressed gently in the centre. During baking, the batter will rise almost to the top of the pans and be domed in the middle, but this will lower just before they are ready. Right after removing the cakes from the oven, run a knife around the edge of the pan and unmold onto a cooling rack. Remove parchment and re-invert so cakes can cool right side up.

For the topping, I went with the recipe from Leite's, as it just looked better and used evaporated milk instead of condensed, meaning I didn't need to make another trip to the grocery store. I had extra, as I didn't cut my cake into 4 layers. It'd make a great topping or filling for cakes, cookies or cupcakes, if you don't eat it all with a spoon.

Coconut-pecan topping

Source: Leite's Culinaria

4 large egg yolks
One 12-ounce can evaporated milk
1 cup granulated sugar
1/4 cup packed light brown sugar
6 tablespoons unsalted butter, cut into 6 pieces
1/8 teaspoon salt
2 teaspoons vanilla extract
2 1/3 cups sweetened shredded coconut
1 1/2 cups (finely) chopped pecans, toasted 

1. Whisk the yolks in a medium saucepan; gradually whisk in the evaporated milk. Add the sugars, butter, and salt and cook over medium-high heat, whisking constantly, until the mixture is boiling, frothy, and slightly thickened, about 6 minutes.

2. Transfer the mixture to a bowl, whisk in the vanilla, then stir in the coconut. Cool until just warm, cover with plastic wrap, and refrigerate until cool or cold, at least 2 hours or up to 3 days. (The pecans are stirred in just before cake assembly.)

To assemble cake:

1. Stir pecans into filling. Slice layers in half horizontally, using a serrated knife, if desired. Top each layer with a generous amount of filling and top with another cake layer. Spread more filling on top of cake.