The chocolate cake that could

FROSTED SOURDOUGH CHOCOLATE CAKE 

I tasted this cake the day it was baked and frosted, and wondered what I could do with a tasteless 18cm square cake, minus a slice – perhaps crumble it up, add a few other ingredients and turn it into chocolate truffles?

I was disappointed that it had taken two days to make and turned out... dull. What a waste of time and effort.

Well, the saying good things come to those who wait was never more apt in this case. The next day, as I sliced up the cake to put it into smaller containers for freezer storage, I tasted my second piece from the slab.

Just as you can't rush a sourdough starter, time is what was needed for the flavour of this cake to emerge. And it certainly struck the right note. The cake didn't end up in the freezer, and instead was well received by everyone who tasted it so, yay!

Making the cake

For the cake, I used the recipe from King Arthur Flour, but with slight modifications. As with most things sourdough, this cake starts with a well-fed starter. After the first feeding, milk, plain flour and sugar are added and the mixture is formed into a soft dough. It only needs to be left at room temperature for a couple of hours according to the original recipe, but I didn't have time to bake that day and put it in the fridge overnight.

The next day, the dough had risen substantially. Out of the fridge, it  rested for about an hour before I combined it with the rest of the ingredients. The mixing takes a bit of effort because of the consistency of the batter. I would describe it as thicker than a creamed cake batter, but almost dough-like, although it is wetter than a high-hydration bread dough. But the two parts will come together after some folding with a rubber spatula, and then it flows out of the mixing bowl easily into the baking pan.

Making the frosting

The frosting comes from Tasty Kitchen and is called "That's The Best Frosting I've Ever Had". I must say, it is very good, and I will be using it for other cakes in the future.

Sourdough Chocolate Cake

12-16 servings

Cake

Based on a recipe from King Arthur Flour and scaled down

½ cup “fed” sourdough starter

½ cup whole milk

1 cup plain flour

¾ cup caster sugar

½ cup coconut oil

1 tsp vanilla extract

½ tsp salt

¾ tsp baking soda

6 tbsp unsweetened cocoa

½ tsp instant coffee or espresso powder

1 medium egg

Combine the “fed” starter, milk, and flour in a large mixing bowl. Cover and store in the refrigerator overnight or let rest at room temperature for 2-3 hours. It won’t necessarily bubble, but it may have expanded a bit.

Preheat the oven to 180°C. Lightly grease and base line an 18cm or 21cm square pan.

In a separate bowl, beat together the sugar, oil, vanilla, salt, baking soda, cocoa and espresso powder. The mixture will be grainy.

Add the egg, beating well.

Combine the chocolate mixture with the flour mixture. Fold the two mixtures together until smooth with a rubber spatula. It may take a little effort as the flour mixture is quite thick. Make sure no chunks of starter dough remain.

Pour the batter into the prepared pan.

Bake the cake for 30 to 40 minutes, until it springs back when lightly pressed in the centre, and a cake tester/toothpick inserted into the centre comes out clean.

Remove the cake from the oven, and set it on a rack to cool.

Coffee Frosting

Adapted and scaled down from “That's The Best Frosting I've Ever Had” recipe at TastyKitchen. Makes about 1 cup.

½ cup whole milk

2½ tbsp plain flour

½ tsp coffee extract

110g unsalted butter, softened

½ cup caster sugar

Combine the milk and flour in a saucepan over medium heat and whisk constantly until thick. Remove from the heat and let cool to room temperature. Add the coffee extract once cooled.

In the bowl of a stand mixer with the paddle attachment, cream the butter and sugar until light and fluffy. Make sure the sugar is dissolved and the mixture is not at all grainy. Add the cooled milk mixture and beat very well. It may look separated – keep beating until fully combined. It should be fluffy and light, similar to whipped cream.

Chocolate Drizzle

From KingArthur Flour

⅓ cup semisweet chocolate chips

1 tbsp milk

1 tbsp corn syrup

Combine the chocolate chips, milk, and corn syrup in a microwave-safe cup. Microwave till the chips soften, then stir till smooth. Alternatively, use a heat-proof bowl over a pot of simmering water.

Assembly

Frost the top of the cake and drizzle/drip the chocolate over the icing. The lines can also be turned into feathers: Use a toothpick or the tip of a knife to drag the lines in one direction, then alternate the direction for the next drag.