Early last week, my colleague Marzyeh invited me to an end-of-summer party she and her husband Eric were holding on Saturday at the picnic area outside their apartment building. They were providing (and Eric was grilling) the protein, but they asked guests to bring a side dish, and I figured a cake would be welcome. I had some leftover ingredients that I needed to use up — notably, 5 oz of pasteurized egg whites, which could be used to make more buttercream, and a cup and a half of heavy cream, which could be used to make some chocolate ganache. Since I had just made (and written up) a whole-wheat cake from King Arthur Flour’s Whole Grain Baking, my fingers naturally landed on “Classic Butter Cake” (p. 368), a vanilla butter cake made with whole wheat pastry flour and other ingredients I already had in my pantry. (I would just have to buy some plain lowfat yogurt, used as the liquid phase in this recipe.)

The frosting would be the chocolate variation of Italian meringue buttercream from the same cookbook, except (since I had five ounces of egg whites) I would scale everything up by 25% — and again, the other ingredients were all standard pantry fare. I didn’t want to use the buttercream as a filling, however, since that wouldn’t use the leftover cream — I needed a whipped ganache filling. My first reference was to Alice Medrich’s Seriously Bitter Sweet, and checking the index I found several options starting on page 189. Intriguingly, she has a hazelnut-flavored version, using gianduja, which would nicely complement the chopped toasted hazelnuts I was planning on covering the circumference of the cake with, but unfortunately it called for twice as much gianduja as I had, and the local Whole Foods stores where I used to buy it have completely screwed up their chocolate selection recently, making many formerly dependable items special-order-only. So I would have to make regular (bittersweet chocolate) whipped ganache instead, and I could perhaps add some ground hazelnut to that, but it wouldn’t be the same. (On further reflection — too late for this cake! — it occurred to me that I could steep some chopped hazelnuts in the cream overnight, the way Medrich does for mint, which would give additional hazelnut flavor. Adding a hazelnut liqueur was out of the question for multiple reasons.) One fly in the ointment was that Medrich’s recipe calls for 2¼ cups of heavy cream, and I only had 1½. Rather than trying to scale down the recipe — I figured that the specified yield would actually be the right amount for a three-layer cake — I broke down and bought more cream. (Now I have a quarter cup of leftover cream, which at least isn’t as much potential waste as a cup and half!)

Both the buttercream and the ganache keep in the refrigerator for a few days, so I made the buttercream on Wednesday night, the ganache on Thursday, and the cake layers on Friday, with the final assembly very late Friday night so the frosting on the cake would have a chance to set up in the refrigerator overnight. Here’s how Friday’s baking went:

The King Arthur “Classic Butter Cake” recipe is a really simple one. Like most of their whole-wheat cake recipes, it calls for a mixture of whole-wheat pastry flour (7⅝ oz or 215 g) and regular all-purpose flour (4¼ oz or 120 g). Two sticks of butter (225 g) and 10½ oz (300 g) of granulated sugar form the base of the cake, along with four whole eggs, two teaspoons of vanilla, and one teaspoon of salt. The leavening is half a tablespoon of baking powder, along with a cup (240 ml) of plain lowfat yogurt and a half teaspoon of baking soda to neutralize the lactic acid.

This cake is constructed by the butter-cake variation of the creaming method: first butter and sugar (and in this case, salt) are creamed together, then eggs are beaten into the butter-sugar base, and finally the dry ingredients are added, alternating with the remaining wet ingredients (in this case yogurt and vanilla, mixed together). The photo above shows an early stage of the batter, after creaming and the incorporation of all four eggs.

The overall yield of the recipe is about 1300 grams of batter; this can be divided into nine-inch round cake pans for a two-layer cake, into eight-inch cake pans for a three-layer cake, or into a 9×13 rectangular baking pan to make a sheet cake (or to cut into other shapes). I made three layers because, as my officemate Linda put it, it just looks more impressive — and it’s not much additional work. I used the scale to portion about 430 g of batter to each of three parchment-lined baking pans, and smoothed off the tops using an offset spatula. I baked all three in a 350°F (175°C) oven for about 25 minutes, opening the oven after about 15 minutes to shuffle the pans around.

For this cake, I bought some “cake strips”. These are nothing more than a textile that wraps around the side of each cake pan after being saturated with water; the theory is that they keep the outer edges of the cake cooler, so they don’t form a crust before the center of the cake sets, thereby preventing “doming” and also eliminating the annoying hard crust that has to be trimmed off. You could just make them yourself by cutting strips of terrycloth and holding them on with a pin, but I’m lazy so I just bought these, which have a hook-and-loop fastener.

So how well did the cake strips do? Not bad, I’d say, but that cake on the left still looks a little odd — my oven isn’t a very good one, isn’t especially level, and probably has hot and cold spots that rotating the pans won’t fix. Or maybe that pan just got filled a bit unevenly. Perhaps all of these things.

In the side view you can see how runty that leftmost layer is. I decided to cut that layer to flatten it, flip the cut side to face down, and make it be the middle layer so most of the imperfections would be hidden by the creamy ganache filling.

After freezing the cake layers for 15 minutes, I whipped the ganache filling, adding about 35 grams of ground hazelnuts in the process. (The ground hazelnuts I didn’t make intentionally, but just sieved out of chopped hazelnuts.) That complete, I weighed out the ganache and the buttercream so I’d have a handle on the nutritional data for the finished cake — the ganache came to 639 g, but only 615 g would make it into the cake (the rest was stuck to the bowl and utensils, then eaten by the baker), and out of 836 g of chocolate buttercream, only 354 g was needed to frost the cake (the remainder was far too much to eat, so it went into the freezer — it can be used to frost something else, like cupcakes, later this year.) I put half of the whipped ganache on top of the bottom layer before stacking the middle layer on top. I used the cake stand here merely to raise the level of the cake to a more comfortable working height.

Especially when the layers are a bit uneven, it’s important to press down on each successive layer to fully seat it in the filling — but this will cause the filling to squeeze out, so you then have to come back with a spatula to redistribute the excess into any voids or gaps that are left.

Now all three layers are fully assembled, and the only thing remaining is to frost the cake with buttercream….

As I’ve noted before, I’m lousy at tasks requiring either patience or fine motor control. Luckily, for bakers, there’s an easy way to cover up a sloppy frosting job:

Oh look, chopped nuts! Nobody will ever know what a terrible job I did of frosting the cake! I kept careful track of the nuts as well, and determined that this treatment used only 145 g of chopped hazelnuts — about half of what I started with, so there is clearly a need for more hazelnut recipes in the future.

Everybody at the party loved the cake, and I was pretty happy with how it turned out, too. I was however left wondering about the prospects for upping the chocolate flavor (and color) of the buttercream frosting; I didn’t feel like it really expressed “CHOCOLATE!” in the way that I would have liked, particularly when combined with a vanilla cake like this. (It would certainly be fine in combination with a cake that packs its own chocolate flavor.) I did leave two thirds of a slice of cake behind when I left; I couldn’t stick around to the end as I had already overeaten and people were still showing up with more food. Now on to Sunday’s originally scheduled cake….

Nutrition

For the cake as presented

In making this cake, I used 615 grams of the whipped chocolate ganache (split between the two middle layers), 350 grams of the chocolate-flavored Italian meringue buttercream (8.5 servings) as presented, and 145 grams of chopped toasted hazelnuts. Figures are subject to inaccuracy due to double rounding.

For the plain butter cake

The butter cake recipe makes approximately 1300 grams of uncooked batter, which gives 16 servings as a two-layer 9″ cake or a three-layer 8″ cake.

For the whipped bittersweet chocolate ganache with hazelnuts

I departed from Medrich’s formula by using two tablespoons of raw wildflower honey rather than the white sugar she specifies, and adding 35 grams of ground toasted hazelnuts. For the chocolate I used Valrhona Guanaja. The recipe makes enough to fill one three-layer cake or two two-layer cakes.

For the chocolate flavored buttercream frosting

The serving size below is based on using the entire recipe to fill and frost a three-inch layer cake. This computation is based on scaling the King Arthur recipe by 125%, except that all of the additional fat was palm oil vegetable shortening rather than additional butter.