Whisk the egg whites in a grease-free bowl until they are stiff. (Test if they are ready by upturning the bowl. If the egg whites slide around, they need to be whisked a little more; if they stay in place, they are ready.)
Whisk in the sugar 1 tablespoon at a time until it is all mixed in. Mix together the vanilla extract, cornflour, coffee granules and vinegar and fold into the meringue along with the chocolate chunks.
Line a baking sheet with nonstick baking paper. Dollop 8 large spoonfuls of meringue on to the sheet. Bake in a preheated oven, 150°C (300°F), Gas Mark 2, for 1 hour. Cool.
Serve the meringues on individual plates, each with a spoonful of yogurt and a drizzle of honey. Cut a cross in the top of each fig and gently squeeze it at the base to open it up. Put 1 fig on each plate to finish.