I’m only calling it “cake” to be polite.

This is so outrageously dense, dark and fudgy that I’m only calling it “cake” to be polite. Even at this tiny scale, made in my little springform pan, I also have to admit that it’s pretty full-on to be classified as “for one”, although half is about equal to a slice of ordinary-sized cake and it will keep, perfectly well, for three or four days. Please mentally insert a winky-faced emoticon here.

Toblerone is a lovely chocolate to cook with as it brings its notes of honey and little pieces of almondy nougat to the party, but feel free to substitute whatever chocolate you like.

The world of cocoa powders is something of a minefield, so I offer you this advice: use Dutch-process cocoa. Cutting to the chase, it tastes better and means you don’t have to add baking powder.

Finally, if the technique is new to you, don’t panic about whisking and folding in an egg white. If you have an electric mixer with a balloon whisk, use that to beat the white then take it off the mixer and use it to gently incorporate the white into your cake mix without knocking out too much air. Works every time.

Tiny flourless Toblerone cake

Serves 2.

50g (2 oz) Toblerone
50g (2 oz) butter
1 tablespoon espresso coffee (or ½ teaspoon instant coffee dissolved in 1 tablespoon boiled water)
1 tablespoon cocoa powder, plus extra for dusting
1 egg
45g (¼ cup) caster (superfine) sugar
55g (½ cup) almond meal (ground almonds)

Set your oven to 180°C (350°F). Butter a small (10cm, 4 inch) springform cake pan, line the base with a circle of baking paper and dust the sides with a little cocoa powder.

Put the chocolate and butter in a small bowl and microwave on medium for one minute or until melted. Stir in the coffee and cocoa powder and set aside.

Separate the egg into two small bowls. Add the sugar to the yolk and, using a handheld electric mixer, beat until pale yellow and creamy.

Add the almond meal and the chocolate mixture to the yolk bowl and beat together just long enough to combine it. Wash and dry the beater.

Whisk the egg white until soft peaks form. Put about a third of it into the chocolate mixture and stir in to slacken the mixture. Add the rest of the egg white and fold it in gently (see note above) until combined.

Pour the batter into your prepared pan and bake for 35 minutes. The top should just be starting to crack a little when it’s ready; test by inserting a skewer (or a stick of dry spaghetti) and looking for moistened crumbs.

Take it out of the oven and allow to completely cool before removing from the pan. Dust with cocoa powder.