Prinzregententorte — Bavaria's seven-layer chocolate cake

i. Origin & history

In 1886, after the death of King Ludwig II and the declaration that his brother Otto was unfit to rule, their uncle Luitpold became Prince Regent (Prinzregent) of the Kingdom of Bavaria. His regency, which lasted until his death in 1912, is remembered in Bavaria as a golden age of prosperity and culture — the Prinzregentenzeit — and Munich is full of places named after him, from the Prinzregentenstraße to the Prinzregententheater.

The cake was created in his honour at around the start of his regency. Credit is most often given to Heinrich Georg Erbshäuser, a Munich court confectioner, although other Munich pastry makers have been named, and the precise date and creator cannot be confirmed. What is certain is that it became one of Munich's signature cakes and has been made by the city's confectioners ever since.

The layers carry a political meaning. The usual explanation is that they represented the administrative districts (Regierungsbezirke) of the kingdom. In Luitpold's time Bavaria had eight, including the Palatinate west of the Rhine, and early versions of the cake are said to have had eight layers. After the Second World War, the Palatinate became part of the new state of Rhineland-Palatinate, and the cake settled at seven layers to match the seven districts of modern Bavaria. It is a good story and widely repeated, though the documentary evidence for the original eight is thin.

Prinzregententorte belongs to the family of thin-layered Central European cakes, with the Hungarian Gerbeaud and Dobos torte and the Russian medovik. It is sometimes compared with the Dobos torte, which also has many sponge layers and chocolate buttercream; the Dobos, however, is crowned with a hard caramel top, while the Prinzregententorte has a smooth chocolate glaze.

ii. Why each layer is baked separately

The beauty of a Prinzregententorte is in its cross-section: seven even, thin layers of pale sponge alternating with seven equally thin stripes of chocolate cream. That precision is achieved by baking each layer separately, spread thinly over a circle on baking paper, rather than baking one thick sponge and slicing it. Thin layers bake in minutes, stay moist and are all the same thickness.

The sponge is a Wiener Masse, a Viennese-style sponge of whisked eggs, sugar and flour with a little melted butter. The butter keeps the thin layers supple, so they can be handled and stacked without cracking. Each layer is spread about 3–4 mm thick and baked at a high temperature, 200 °C, for six to eight minutes, until just set and pale golden.

The chocolate cream is traditionally a German buttercream (Deutsche Buttercreme): a chocolate custard beaten into soft butter. It is lighter and less sweet than a buttercream made with icing sugar, but it must be made carefully, with the custard and butter at the same room temperature, or it curdles. Melted dark chocolate gives it its deep flavour and firm set.

The finish is a thin layer of warm apricot jam over the top, which seals the surface so the glaze sets smooth and glossy, followed by a dark chocolate glaze. The cake is then chilled so that the buttercream firms and the layers can be cut cleanly.

iii. Ingredients

Makes 16 servings · scroll the side panel to adjust

• 6 eggs, room temperature
• 180 g caster sugar (sponge)
• 1 pinch salt
• 1 unwaxed lemon, finely grated zest
• 150 g plain flour
• 30 g cornflour (sponge)
• 60 g unsalted butter, melted and cooled
• 500 ml whole milk
• 100 g caster sugar (cream)
• 40 g cornflour (cream)
• 2 egg yolks
• 150 g dark chocolate (60–70%), melted (cream)
• 250 g soft unsalted butter (cream)
• 3 tbsp apricot jam, warmed and sieved
• 200 g dark chocolate (glaze)
• 30 g unsalted butter or 1 tbsp neutral oil (glaze)

The sponge is a light Wiener Masse; cornflour makes it finer and more tender, and melted butter keeps the thin layers flexible. The chocolate cream is a German buttercream; you can replace it with a French or Swiss meringue buttercream flavoured with melted chocolate, or with a chocolate ganache whipped with butter. Use a good dark chocolate for both cream and glaze: the cake depends on it. The apricot jam layer is traditional and gives the glaze a smooth base.

iv. Method

1. First make the custard: heat 400 ml milk with the sugar. Whisk the remaining 100 ml milk with the cornflour and yolks, whisk in the hot milk, return to the pan and cook, whisking, until thick and bubbling for 1 minute. Stir in the melted chocolate. Press cling film onto the surface and cool to room temperature.
2. Heat the oven to 200 °C (390 °F), conventional heat. Draw a 24 cm circle on each of seven sheets of baking paper and turn them over.
3. Whisk the eggs, sugar, salt and lemon zest for 8–10 minutes until very thick and pale. Sift over the flour and cornflour and fold in, then fold in the melted butter.
4. Spread about 1/7 of the batter (roughly 90 g) evenly over each circle with a palette knife. Bake one or two at a time on a baking tray for 6–8 minutes, until set and pale golden. Slide onto a rack and cool. Trim each layer to an even 24 cm circle using a plate as a guide, then peel off the paper.
5. Beat the soft butter for 3–4 minutes until pale and creamy. Add the room-temperature chocolate custard a spoonful at a time, beating well after each addition, to a smooth cream.
6. Put the first layer on a cake board inside a 24 cm cake ring or springform ring. Spread with a thin, even layer of chocolate cream. Repeat with the remaining layers, finishing with a sponge layer, and keep some cream for the sides. Chill for 1 hour.
7. Remove the ring and cover the sides thinly with the remaining cream. Brush the top with the warm apricot jam and chill for 30 minutes.
8. Melt the chocolate with the butter, cool slightly, and pour over the top of the cake, spreading it to the edges and down the sides. Chill for at least 2 hours before slicing with a hot knife.

v. Tips & common mistakes

• Weigh the batter for each layer. Equal weights mean equal layers, which is the whole look of the cake.
• Do not overbake the sponge layers. They need only a few minutes; overbaked, they dry out and crack when stacked.
• Keep the custard and butter at the same temperature. If the buttercream curdles, warm the bowl briefly over hot water and beat again; if it is too soft, chill for 10 minutes.
• Spread the cream thinly. The cream layers should be about as thick as the sponge. Too much cream makes the cake heavy and the layers slide.
• Use a cake ring to assemble. It keeps the stack straight and even. Without one, the layers tend to drift.
• Chill well and cut with a hot knife. A cold cake with a warm, wiped blade gives clean slices with distinct layers.

vi. Variations

Munich confectioners make the cake with different chocolate creams: some use French buttercream, others a chocolate ganache beaten with butter, and some add a little nougat or hazelnut praline to the cream. Some versions leave out the apricot jam. There are also Prinzregententorte slices made on a tray and cut into rectangles, and modern versions decorated with a chocolate plaque or the Bavarian crest.

Its relatives include the Hungarian Dobos torte and Gerbeaud cake, the Russian honey cake medovik, and the German Schwarzwälder Kirschtorte and Donauwelle. For another cake named for nobility, see the Swedish prinsesstårta.

vii. Serving & storage

Prinzregententorte is served chilled or cool, in thin slices, with coffee in the afternoon. In Munich it is a cake for birthdays, anniversaries and Sunday visits, and it is a fixture of the city's traditional cafés and confectioners. It needs no accompaniment, though a little lightly whipped cream is sometimes offered.

Keep it covered in the refrigerator, where it keeps for up to five days; the flavour improves after a day as the layers settle. Take it out about 20 minutes before serving so the buttercream softens slightly. It freezes well for up to two months, whole or in slices; thaw overnight in the refrigerator. The sponge layers can be baked a day ahead and stored, layered with paper, in an airtight container.

ix. More from Austrian & German

• Schwarzwälder Kirschtorte — Black Forest gâteau
• Donauwelle — Danube wave cake
• Punschkrapfen — Viennese rum cakes
• Kardinalschnitten — meringue and sponge slices
• Gerbeaud Cake — Hungarian layered slice
• Medovik — Russian honey layer cake