The complaint that pastry lovers most often levy again Sacher torte is that it’s dry. You hear that a lot from people returning from trips to Vienna: I went to the Sacher hotel and ordered Sacher torte and I was so disappointed…it was so dry. Is that true? No and yes. Defenders of Sacher torte maintain that it’s only dry in comparison to the hyper-rich, hyper-moist pieces of confectionary that pass for pastry in the modern world, especially here in America. I think there’s great merit to that argument. However if Sacher torte isn’t a little bit dry, why is it tradition that it must always — always — be served with a good-sized dollop of whipped cream on the side? For what is whipped cream for other than to enrich and lubricate? The dryness contingent has a point.
Personally, I prefer to think of Sacher torte as “firm”, for it is certainly that. Some have argued that the firmness was intentional on Franz Sacher’s part, meant as a tribute to Metternich’s masculinity and dominating will. That idea emits the distinct odor of rationalization to me.
So what gives Sacher torte its uniquely firm texture? The answer is: foam. The cake that forms the basis of Sacher torte is sponge cake, and sponge cakes are leavened with egg white foams. The trouble with egg white foams is that they are mostly air. Apply heat to them and they tend to dry out. That’s why a good Sacher torte recipe has plenty of egg yolk and/or butter in there. The fat helps keep the cake supple and moist. Yet there’s a limit to how much fat you can add to a sponge cake before it gets so heavy the foam can’t lift it. Sacher torte batter has about as much fat as you can reasonably put into a foam-leavened layer of cake and still have it rise.
That hasn’t been good enough for more than a few pastry chefs over the years, which is why many have sought to “improve” it with various additions and/or modifications. None of them are considered “authentic” by Viennese purists, of course. A real Sacher torte adheres strictly, absolutely to the original recipe (though it’s technically still a Sacher hotel and/or Demel’s secret). Everything else is a “Sacher-style” torte, as my friend Gerhard is very quick to remind me.