There is something that feels literally magical about the start of blood orange season. A few weeks after the excitement of Christmas and New Year’s has died, when we’ve glumly settled into the January doldrums, being beset by cold toes precludes us from wearing anything but big clumpy shoes, and slushy snow feels rather less than miraculous, the blood oranges suddenly … appear. There they are at the greengrocer’s, putting clementines, humdrum navel oranges and even Sevilla oranges to shame. They’re like visitors from a superior planet. Blood oranges would be irresistible even if they weren’t so glorious-looking, but slicing open a blood orange to reveal its saturated pomegranate-red flesh gives me an almost voyeuristic thrill. So beautiful, so delicious.
This year, like last, I threw my own birthday party (I highly recommend it; you get exactly the party you want) and by all measures, it was a success, with lots of wonderful food that I’ll be blogging over the next few weeks. This dark chocolate and blood orange cake was my birthday cake, which is why in the photos it’s looking a bit the worse for wear. (None of us would look our best after spending a night in the fridge covered with aluminium foil.) I love this cake. It is dense, moist, and fudgy, deeply orange-y, and boozy. There are five chopped blood oranges in the cake, the flavor of which as they’re baked becomes concentrated and almost alcoholic, like the cherries in black forest cake. I normally am not a fan of self-rising flour, as I don’t think it actually rises all that well, but in this case that density really works.
In the UK, I find that it is almost impossible to locate really good quality unsweetened cocoa powder for baking. (And Dutch processed? Forget about it.) So I used Whittard 70% dark chocolate drinking cocoa. I phoned Whittard today to find out how much sugar the cocoa contains, and was told that the powder is 31.2% sugar. I’ve adjusted the quantities below to reflect that percentage (i.e., the quantities are for unsweetened cocoa powder), but either way I recommend you use high-quality cocoa with a high cocoa percentage. I drizzled the individual layers with Cointreau, but that’s strictly optional. Since this was a birthday cake, I covered it in a ganache so I could write “Happy Birthday to ME” on it, but if I made the cake again, I’d cover the whole thing in frosting since the slightly orange-y frosting was such a lovely contrast. I made an Italian meringue buttercream frosting (recipe follows) which is lighter and fluffier than Swiss meringue buttercream. If you want something richer and thicker and more substantial, here is a link to a Swiss meringue buttercream recipe. Or you can dispense with frosting altogether, bake this in a square pan, and serve it with crème Anglaise. Finally, one of my friends very sweetly told me that he would have liked my cake even better if there were lots and lots of frosting between the layers. Yes, I was a little stingy. Don’t make the same mistake.
You will need:
A cake pan (or two), preferably springform
Baking parchment or silicone baking paper
A standing or handheld mixer
A rubber spatula and/or palette knife for decorating the cake
A small heavy-bottomed saucepan
A candy thermometer or (as explained below) nerves of steel
(These quantities are for a 9 and ½ inch x 2 and ½ inch cake pan, which I made into a three-layer cake; you can also bake this in two cake pans and make a four-layer cake. The weights are as exact as my kitchen scale.)
For the cake
375 grams soft unsalted butter (13.2 ounces, or a little over ¾ pound), plus additional butter for the cake pan
450 grams sugar (15.8 ounces, or approximately a pound)
1 teaspoon vanilla extract
5 large eggs or 6 medium eggs
300 grams sifted self-raising flour (10.6 ounces)
140 grams sifted unsweetened cocoa powder (4.9 ounces, or slightly more than ¼ pound) (try to get 54% dark or higher; 70% dark is what I used)
½ teaspoon salt
Zest of two blood oranges
Flesh of five blood oranges, supremed, and any juice reserved (To supreme an orange, using a sharp knife, slice the ends off of either side and then carve away the skin from the flesh, trying to remove all the white pith. Then carefully slice the segments away from the membranes that separate them. I find it is easiest to slice one side of each segment and then you can pull the segment easily away from the membrane on the other side.)
3-5 tablespoons Cointreau (optional)
For the Italian meringue buttercream frosting
5 egg whites, at room temperature
250 grams (8.8 ounces) sugar, divided
½ cup water
226 grams soft unsalted butter (two sticks), cut into small chunks
Juice of one blood orange + one tablespoon sugar, reduced to the consistency of maple syrup over a low flame and chilled
For the cake
Preheat your oven to 350 degrees Fahrenheit (180 degrees Celsius). Use an oven thermometer if necessary to ensure accuracy.
Line the base of a springform 9.5 inch x 2.5 inch cake pan (or two cake pans) with baking parchment or silicone baking paper, and then grease the pan and parchment with butter.
Combine the flour, cocoa, and salt in a mixing bowl.
In another bowl, cream together the butter, sugar, zest, and vanilla extract until fluffy. Add the eggs one by one, beating thoroughly after each until it is fully incorporated. Fold this fluffy mixture into your dry ingredients until fully mixed, then fold in the blood orange pieces and reserved juice. Spread this batter in your prepared cake pan(s) and bake in the center of your oven until the interior of the cake registers 205 degrees Fahrenheit (96.1 degrees Celsius) on a thermometer. (I find this to be more reliable than jabbing your cake with a wooden stick.) Baking the cake in a 9 and a half inch pan took me nearly an hour and a half; divided between two pans I expect it would be more like 50 minutes.
Transfer cake to a wire rack and let cool for about 10 minutes, then loosen the sides of the springform pan and let cool completely.
For the Italian meringue buttercream frosting
Combine 200 grams (1 cup) of the sugar in a heavy-bottomed saucepan with ½ cup water, and heat over medium heat, without stirring. You can swirl the pan occasionally to catch any crystals that may adhere to the edge. You want to heat the sugar to 245 degrees Fahrenheit (118 degrees Celsius). It is much easier to do this with a candy thermometer, but you can also heat the syrup until a bit dropped in some cold water forms firm balls. This takes nerves of steel.
While the sugar syrup is heating, start beating the egg whites in a clean stainless steel bowl. When they’ve become creamy add the remaining 50 grams (1/4 cup) sugar and continue beating until the egg whites are stiff. When your sugar syrup has reached the desired temperature, turn the speed on your beaters to high and drizzle the syrup in a thin stream against the side of the bowl (not directly into the egg whites, if you don’t want to cook the egg whites and ruin your frosting). Continue beating until the bowl is completely cool to the touch, about 10-15 minutes. Your egg whites will be very stiff and glossy.
When your egg whites are completely cool (again, don’t rush this or your butter will melt and your frosting will collapse), beat in the butter one piece at a time until it is completely incorporated and you have a thick, luscious, creamy frosting. This lovely blog post here has a great pictorial guide on making Italian meringue buttercream, and I used her proportions.
Drizzle in the blood orange juice, beating all the while.
To frost your cake, cut the cake carefully with a bread knife into layers and place onto a board covered with parchment paper. Drizzle each layer with 1-2 tablespoons of Cointreau. Frost generously between the layers using a rubber spatula or palette knife, and then frost the top and sides. If you use the bottom of the cake as your top layer you’ll have a nice smooth surface. Transfer to a clean plate when done.