Happy birthday to Sacher torte

One of the world's most famous cakes, the Sacher torte, has just celebrated its 175th birthday. (If you think that an inanimate object can't celebrate a birthday, let me tell you that there was a party for the cake on 12 April at Hotel Sacher in Vienna, and that it included a serenade by an opera star!)

Sacher torte is two layers of a dry, dense chocolate cake, sandwiched together with apricot jam and enrobed in dark chocolate. It was invented by Franz Sacher in 1832 and the trademark registered by the Hotel Sacher, which keeps the original recipe locked in its safe.

I first encountered Sacher torte when I was 15 and my family travelled around Europe and the UK for three months. While in Vienna, Dad refused to pay the outrageous tourist prices at the Hotel Sacher, so we missed our opportunity to taste the cake at its place of origin. But a week or two later, my sister celebrated her 12th birthday in Lucerne, Switzerland. We ate dinner at a restaurant with a beautifully decorated and frescoed front and the birthday cake was a Sacher torte, bought from a bakery earlier in the day, and brought out by the restaurant staff decorated with sparklers. I remember it as deliciously rich cake, with small slices being enough to satisfy.

Dad was right about the tourist prices at Hotel Sacher. About 15 years later, when my sister and I were visiting Vienna again, we paid 12 euros for a slice of Sacher torte and two hot chocolates. We enjoyed it but I'm not sure any chocolate cake is worth the equivalent price of a Cheap Eats meal in Melbourne!

Although the original recipe is a closely guarded secret, plenty of chefs have produced their own versions, and it is an easy cake to make at home. I use Jill Dupleix's version. It makes for an indulgent afternoon tea or a glamourous dinner party dessert.

SACHER TORTE

150g plain flour
50g bitter cocoa powder
6 eggs (60g each)
180g sugar
1/2 teaspoon vanilla extract
150g apricot jam
100g good-quality chocolate
100g butter, chopped

Preheat the oven to 180 degrees. Butter a 23cm diameter springform cake tin.

Sift the flour and cocoa into a bowl and set aside.

Separate the eggs. Beat the yolks and sugar until so thick and creamy that it forms ribbons when you lift the beaters. Stir in the vanilla extract.

Beat the egg whites in a separate, clean, dry bowl until stiff and peaky. Gently fold a little of the egg white into the egg yolk mixture to lighten it, then fold in the remaining egg whites.

Gently fold the sifted flour and cocoa into the mixture, adding two tablespoons at a time. Transfer the quite thick mixture into the cake tin and bake for 30 to 35 minutes, or until a skewer inserted into the centre of the cake comes out clean. Cool in the tin for 10 minutes, then remove from the tin and cool completely.

To assemble, cut the cake into two equal rounds. Place the base on a wire rack over a baking tray. (If the top has risen considerably, cut off the domed part to level the top). Warm the apricot jam in a small saucepan and spread a thin layer on top of the bottom half and its sides. Replace the top half and spread the top and sides with jam (you might not use it all).

Melt the chocolate and butter in a heatproof bowl set over a saucepan of simmering water. Stir until glossy and smooth, then set aside for a couple of minutes. Pour the icing over the top of the cake and sides, smoothing sides with a hot palette knife if necessary.

Allow to cool, then set hard in the fridge for an hour or two before serving.

Sacher torte is traditionally accompanied by whipped cream.