Authentic Frankfurter Kranz (German Crown Cake)

Frankfurter Kranz; a cake fit for an Emporer! This crown cake will never fail to impress. A wreath-shaped European biscuit-sponge cake, filled with decadent buttercream and jam and decorated with caramelized nuts. The buttercream peaks and raspberries on top suppose to resemble a bejeweled crown. This is not a cake for the modest.

Frankfurter Kranz is one of the traditional dishes from Frankfurt- just like Frankfurter Grüne Soße, Frankfurter Sausages, or Bethmännchen. I grew up near Frankfurt and know this cake well. It is not the fastest cake to make, but the effort is well worth the result.

What is Frankfurter Kranz

Frankfurter Kranz is a classic German buttercream cake. You bake it in a wreath cake mold and then filled with German buttercream. The cake has three layers of biscuit sponge, with layers of jam and buttercream between. Lastly, the cake is covered in more buttercream and coated with caramelized nuts (known as "Krokant" in German).

The top of this opulent cake is decorated with cream swirls, that reflect the peaks of a crown. Finally, these peaks are topped with cherries or raspberries that resemble rubies. Hence it is known as in English: "Frankfurt Crown Cake". In French, it is called "Couronne de Francfort".

History

This cake was created around 1735 by an unknown pastry chef. The first written recipe dates back to the 20th century. [Source: Frankfurt.de]. Frankfurt is in the center of Germany. Since the 16th century, many German Kings and Empires were crowned in Frankfurt.

It is unclear whether this crown cake was actually invented in Frankfurt, or whether the creation wanted to pay tribute to the town as a place for coronations. It is also uncertain which Emporer was to be celebrated because the last coronation in Frankfurt took place in 1711 (Karl VI), which was 24 years before the cake was created.

How to make Frankfurter Kranz

This cake is not the simplest of German cakes to make. At the same time, it is not rocket science. I have made this cake enough times, to point out the challenges. All you need is patience and time to make the perfect Frankfurter Kranz.

Ingredients:

You can find the exact measurement on the recipe card below.

For the cake base

• sugar
• eggs- use medium-sized eggs, and make sure that they are at room temperature. This will help the cake rise.
• corn starch - a great ingredient for biscuit sponges. This will make the cake light and airy. It also prevents the cake layer from breaking when it is being cut.
• flour - you can use pastry flour or cake flour for this cake.
• baking powder (affiliate link)

For the German Butter Cream

• milk whole milk - do not use skimmed milk for the cream, as it will result in a too-thin pudding.
• cornstarch - this gives the pudding stability.
• sugar
• egg yolk - you can freeze the egg whites and use them for Baiser cookies or German coconut macaroons.
• vanilla extract (affiliate link) - if you want you can also cook scrape out a vanilla bean (affiliate link) and add the seeds and pod to the milk.
• butter
• powdered sugar/icing sugar - this will help stabilize the buttercream so it makes it easier to pipe later on.
• turmeric (optional) - adds some color to the buttercream

Caramelized Nuts

• almonds or hazelnuts
• sugar
• butter

For the Filling

• raspberry jam or another jam - a sweet and sour red jam is traditional - but you can replace it with whatever you fancy
• raspberries - or red cherries (use sour cherries or maraschino cherries).

Frankfurter Kranz Recipe: Step by Step

1. Ideally, you make the cake base the day before, or a few hours in advance. The fine-pored biscuit sponge needs time to stabilize, so it does not start to fall apart when being cut.
2. Preheat your oven to 175°C/ 347°F top-to-bottom heat.

3. Using a stand or hand mixer, whisk together the eggs and sugar at a high speed for approximately 10 minutes. This adds air to the dough. The mass should expand and become nice and thick.
4. Combine the cornstarch, flour, and baking powder (affiliate link) and sieve it into the bowl, to avoid any lumps. Add it in little portions to the egg mass, and combine at a slow speed. (If you mix too fast the dough might collapse and end up being too hard).

5. Cover your baking form with butter and dust with some flour. This will help the cake pop out easier after baking.
6. Fill the batter into the cake tin and bake for approximately 30-35 minutes. To test if the cake is done, prick a skewer in the middle. If it comes out clean the cake is ready. Once the cake cooled completely, store it in the fridge until needed.

To make the German Butter Cream

7. Place the cornstarch, vanilla extract (affiliate link), sugar, and turmeric in a bowl with 100 ml (½ cup) of the milk and whisk to a smooth mass, to ensure that no lumps remain.

8. Pour the remaining milk into a small saucepan and bring to a boil, while stirring continuously to ensure the bottom does not burn. Once the milk is boiling, remove it from the heat and pour in your starch mixture. Mix in with a whisk and then place back onto the heat, while stirring continuously. The pudding should thicken up. You do not want the pudding to be too creamy, I prefer a drier consistency for the cream. (see picture)
9. Cool the pudding to room temperature. To prevent a skin from forming, place some cling film/foil on the surface. The pudding and the butter need to have the same temperature, so it's best to keep them in the same room.

10. Once both the pudding and butter are at room temperature, whisk the butter with the powdered sugar for about 3 minutes at a high speed. You will see that the butter has a white sheen.
11. Add in the vanilla pudding spoon by spoon. Whisk on high speed to combine the pudding after each spoon.

To make the caramelized nuts.

12. Put the sugar and butter in a saucepan and, stirring continuously, heat until the sugar and butter have melted.
13. Add the nuts. Stir to coat the nuts with the butter sugar emulsion.
14. Spread the nuts on some baking paper and leave to cool. Wait until it has cooled. Then you can break it into little pieces with a rolling pin (affiliate link), or grind in a food processor.

Assembling the cake

15. The wreath-shaped cake needs to be sliced into three tiers. I like to use a cake leveler like this. Alternatively, take a spool of thread and wrap it equally around the cake. Hold it tight with both hands and pull in opposite directions so it cuts through the middle of the cake and leaves you with two perfectly even layers. Then repeat. Another option is to use a paring knife to score the entire outside edge of the cake halfway up the side. Take the serrated knife and cut through the cake along the indentation made with the paring knife. Use the knife to lift the top layer off of the bottom layer.

15. Save ⅓ of the buttercream for later. Use ⅔ of the buttercream for the filling. On each layer, first spread a layer of raspberry jam, followed by a layer of German Buttercream. You may be able to achieve even layers if you pipe the buttercream onto the cake layers more easily than by spreading it with a pallet knife. Although, both ways are possible.

15. After you filled the cake, place it back in the fridge for 15 minutes. This will help firm up the cake and cream and will make it easier to cover later on.
16. Fill some buttercream in a piping bag (affiliate link) with a star tip to decorate later. Evenly spread the remaining buttercream on the cake. - I like then to place the cake back into the fridge for a further 15 minutes. This will harden the buttercream to avoid the caramelized nuts to get too wet or sliding down the cake. If you are planning to serve the Frankfurter Kranz the next day, only add the caramelized nuts before serving, as otherwise, they might get soggy.
17. I have not found a neat way of covering the cake with the nuts. Gently add some nuts to the palm of your hand and then press onto the cake, until it is covered from all sides.
18. Lastly using the piping bags, pipe little roses on top of the cake and decorate the tips with raspberries. Store in the fridge until serving.

3 Mistakes to Avoid when Making Frankfurter Kranz

• Do not rush the process: it is better to allow the sponge cake to cool, before cutting. Give the pudding and butter enough time to reach the same temperature before making the buttercream, and cool the cake a final time, before adding the caramelized nuts.
• Whisk the eggs for the biscuit sponge long enough, to ensure a light and airy mass. At least 10 minutes. Fold the dry ingredients in gently, and do not mix for too long.
• Leave the caramelized nuts to the end. The nuts become soggy with moisture, so it is best to leave decorating the cake until the end.

How to serve?

In Germany, Frankfurter Kranz is served in the afternoon with a cup of coffee. "Kaffeezeit" is for most Germans between 3 and 5 pm. This is where they meet and enjoy a piece of cake with some coffee and cake.

How to store

Frankfurter Kranz likes it cool. At room temperature, the buttercream might get too soft and soggy. But beware the caramelized nuts can also get soggy - if it comes in contact with moisture. So if you are planning to serve the cake the next day, store it without the nut coating. Apply the nuts shortly before serving.

Leftovers can stay good in the fridge for up to 3 days.

You can also divide the cake into portions and freeze it. Defrost at room temperature.

Recipe