Sachertorte

Sachertorte is a dense chocolate sponge split and coated with apricot jam, sealed under a dark chocolate glaze. It's Vienna's most argued-about cake, invented in 1832 by a sixteen-year-old apprentice named Franz Sacher, and the subject of a decades-long legal fight over which Viennese hotel gets to call its version the "Original."

What it actually is

A dense, only lightly leavened chocolate sponge is baked, cooled and split, with a thin layer of apricot jam spread through the middle and again brushed over the entire outside before it's glazed. The glaze itself is a proper chocolate couverture poured over the whole cake in one smooth pass, left to set into a hard, glossy shell rather than a soft ganache.

The apricot jam is doing real work, not just flavour: it seals the crumb so the chocolate glaze sets clean and glossy rather than sinking in and turning dull.

How it's served

• Unadorned on top, just the word "Sacher" sometimes piped in chocolate.
• With a small mountain of unsweetened whipped cream on the side, never on top of the cake.
• At room temperature, cut into narrow wedges — it's a dense cake, and a thick slice is more than most guests want.

Writing it on a menu

• Flag gluten, egg and dairy; the sponge and glaze carry all three.
• Say whether it's the "Original Sachertorte" recipe with a single jam layer, or a bakery variant with jam through multiple layers, since the difference is a genuine point of contention in Vienna.
• Mention the unsweetened whipped cream it's traditionally served with, since the cake itself is quite plain and not overly sweet.
• Note that it keeps well, being dense and low in moisture, which makes it a reliable make-ahead dessert.