Hofburg Palace, Vienna
 

When I was last in Vienna, I missed out on trying out the Sacher-torte famed in the "City of Music" (just think of one composer out of many: Johann Strauss II). It was available for purchase at International Departures at the airport but I did not fancy hand carrying a cake halfway across the world back to Miri.

My Vienna video clip: https://www.youtube.com/watch?v=jtRehZuB7Do

The cake was concocted in 1832 by Franz Sacher who was only 16 years of age at the time. The Austrian State State Chancellor, Prince Klemens Wenzel von Metternich had tasked his kitchen staff to come up with a an extraordinary dessert for a dinner. Apprentice Chef Sacher stepped up to the task as the Chef was ill that night. And thus was created, this special chocolate sponge-apricot jam-chocolate icing cake.

Not having any plans to re-vist Vienna any time soon, I think that the next best thing now is to bake a close approximation of the Sacher-torte using the best ideas from several recipes which are available (the original recipe is apparently a tightly-held secret and thus what we have outside must be an approximation).

Ingredients

• Couverture chocolate
  This is chocolate with a high content of cocoa butter which is used  for coatings and dipping. Hotel Sacher recommends a cocoa solids content of at least 55%.

• Apricots
  These were not in season so I opted to use the dried variety.
  Try and choose the product which does not have the same color as the fresh fruit because that nice yellow/orange is maintained through the use of sulfite salts e.g. sodium metabisulfite. The later may be a problem to the health of some people: "Sulfites can cause side effects such as abdominal pain, diarrhea, hives, low blood pressure and even life-threatening anaphylaxis, according to a paper published in the winter 2012 issue of Gastroenterology and Hepatology from Bed to Bench. From 3 to 10 percent of people with asthma have a sulfite sensitivity. Such people are even more vulnerable to the many side effects of sulfites" (Livestrong.com, 2021).

Method

• You are making a food product.
  Exercise maximum hygiene/sanitation in all your procedures.

• The addition of sugar and lemon juice helps set conditions which deter spiolage microorganisms. One may be tempted to reduce the amount of sugar in the resulting jam but do note that high sugar content is what prevents jam spoilage. Monitor any stored jams and keep them in a refrigerator.

Apricot jam

You can make as much as you like and keep the extra in the refrigerator. Do this:

• Dice 250 g of dried apricots.

• Add 750 mL of water and leave overnight in the refrigerator to soak.
  This should plump/soften the fruit and also allow any added metabisulfites to leach out.

• The next day, discard a known amount of water and replace it with the same quantity of fresh water (if you wish to get rid of metabisulfites which have leached out from the fruit overnight).

Dried apricots before and after overnight soaking

• Add the juice of 1 large lemon and bring all to a gentle boil.
  Lemon juice is an essential ingredient because it lowers the pH (acidity) (less than pH3.5 is required) of the apricot stew. This then allows the pectins liberated from the fruit to gel and the lowered pH also helps deter the growth of spoilage microorganisms.

Diced apricots at the start of stewing

• Reduce the heat and simmer with stirring for at least 30 mins or until the fruit is as soft as you would like.

• Add 750 g of sugar and stir to dissolve under a low simmer.
  NOTE: This amount of sugar is half of what has been stated in the reference jam recipe. While this is probably more in line with modern concerns about sugar intake, recognize that the resulting jam may not keep for as long before being spoiled.

• Continue summering for at least 20 minutes.

• Now you can test if the jam is ready: Dribble some of the mixture onto the surface of a sloped cold plate. See how it runs - if it does so then it is not ready. If it sets then the jam is ready.

The apricot jam is ready

• The jam can be used as is but some prefer a smooth consistency in which case the jam is pushed through a coarse sieve to macerate the chunkier pieces of fruit. The jam is ready for use in the next step while it is still warm (and therefore runnier).

• Refrigerate any excess for other uses (you may chose not to sieve this portion as use it as a jam spread for example).

Chocolate cake

• Preheat the oven to 180°C. Line the bottom of a 23 cm cake pan with baking paper or butter/flour the bottom of the pan. Sift the flour, baking powder and salt together, set aside.
   

• Cream the butter with half the sugar until light and aerated. Add the egg yolks and vanilla, mix until combined. Mix in the dry ingredients without over mixing. Melt the chocolate and whisk it into the batter.
   

• Whip the egg whites to a soft peak state. Slowly add the remaining sugar and now it whip to a full peak. Fold the egg whites into the batter one third at a time, mixing just just enough to incorporate well.
   

• Pour the batter into the buttered pan, and bake for about 45 - 50 minutes. The cake is ready when the middle springs back when pressed or a cake tester inserted into the cake comes out clean.
   

• Cool the cake on a cake rack and remove from the pan.
   

• Trim the top of the cake to obtain a flat surface (remove the dome).
   

• Slice the cake horizontally into two halves.
  
  Use warm apricot jam for the next steps (warm makes for a runnier consistency).

• Coat the upper surface of the bottom disc with a liberal coating of apricot jam.

• Affix the second disc onto of the bottom disc.

• Coat the upper surface of the top disc with a liberal coating of apricot jam.

• Now coat the sides of the assembled cake.

• Set the coated cake aside on a cake rack for the jam to soak in and also set (while cooling down).

• The coated cake is ready for taking on a chocolate ganache glazing.

Chocolate ganache

A chocolate ganache is made with heavy cream and chocolate whereas chocolate frosting (or icing) is made with sugar and chocolate. I chose to use a ganache instead of frosting because the former has no added sugar. Make it thus:

• Heat 125 g of heavy cream to a simmer

• The add slowly and with constant stirring, 250 g of couverture chocolate (chop bars up or use chips)
  Keep stirring until the mixture smooth and shiny.  If the mixture is too thick you can add some hot water to achieve a runny, pourable consistency. Remove from heat and get ready to pour it over the cake to glaze it.