I made this cake (recipe from Epicurious) for Noel's birthday. It is a fantastic cake, moist but not cloyingly dense, and with excellent crumb. I found the frosting a little too heavy and dark, and think that this might be better with a lighter icing like whipped ganache, but other people in the lab thought it was just right. Make sure that you use a good chocolate - I used a combination of 70% and 85% Lindt Excellence.

Cake

2 cups caster sugar

1.5 cups plain flour (or cake flour if you're in America)

0.75 teaspoon baking soda

0.5 teaspoon salt

1 cup water

2 tablespoons instant espresso coffee powder

115 g dark chocolate, finely chopped

0.5 cup vegetable oil

0.5 cup sour cream, room temperature

2 large eggs, room temperature

1.5 teaspoons vanilla extract

Frosting

1 cup double cream

115 g butter, chopped

0.5 cup sugar

0.25 cup water

2 teaspoons instant espresso coffee powder

0.25 teaspoon salt

450 g dark chocolate

1 teaspoon vanilla extract

Preheat the oven to 160C. Butter two 8- or 9-inch round cake pans and line with greaseproof paper. Lining is essential - these cakes will stick if you don't!

Mix together the sugar, sifted flour, baking soda and salt in a large bowl. In a small saucepan, bring the 1 cup of water to a simmer, then remove from heat. Immediately add the coffee powder and chocolate and whisk until the chocolate is melted and smooth. Set aside to cool for a couple of minutes.

In another bowl, whisk together the vegetable oil, sour cream, eggs and vanilla to blend. Add the chocolate mixture and whisk again to blend well. Add 1/3 of this chocolate/sour cream mixture to the dry ingredients and stir in. Add remaining chocolate mixture in two more additions, stirring well after each addition.

Divide the batter equally between the prepared pans. Gently tap each filled pan on the counter top to burst any air pockets. Bake the cakes until a tester inserted in the centre comes out clean, about 40 minutes. Let the cakes cool in their pans for 5 minutes, then run a knife around the sides of the cakes and turn them out onto wire racks. Cool completely.

While the cake is in the oven, you can make the frosting. Place the cream, butter, sugar, water, coffee powder and salt in a large saucepan over medium heat and bring to a simmer, stirring until butter melts. Remove from heat, add chocolate, and whisk until melted and smooth. If you haven't chopped the chocolate finely enough and it won't melt, you can pop the pan back on the heat for 10 seconds or so at a time while still beating, until it is smooth. Whisk in the vanilla, then pour the frosting into a large bowl. Set aside and cool until thick enough to spread, about 2-3 hours, stirring occasionally.

To construct the cake, place one cake on a plate. Spread 1/3 of the frosting over the cake. Top with the second cake, and spread the remaining frosting over the top and sides of the cake. Allow the cake to stand for 2 hours before serving.

This cake can be prepared one day ahead - just cover and refrigerate, then bring to room temperature before serving.

9 December 2003