Double chocolate meringue tower

Method

1. Heat the oven to 120°C fan/gas 1. Use an electric whisk on medium speed to whisk the egg whites to soft peaks, then increase the speed to high and continue whisking while adding the cream of tartar and caster sugar, a spoonful at a time. When it’s stiff and glossy, whisk in the vanilla extract. Pipe around 18 meringues onto a large baking tray (or 2 trays) lined with baking paper (stick the paper in place with a tiny blob of meringue in each corner). Dust half with cocoa powder. Bake for 1½ hours, then turn off the oven and leave them to cool inside for 2 hours.
2. Meanwhile, whip the double cream until stiff – this will act as the glue when building your tower. Melt the white and dark chocolate separately in heatproof bowls (either using short pulses in a microwave or set over a pan of hot water on a gentle heat – don’t let the water touch the bowl). Add the milk and sugar to a small saucepan and bring to the boil. As soon as it’s boiling, pour the milk over both bowls of melted chocolate, aiming for half in each. Whisk until smooth.
3. To build the tower, arrange some meringues on the base of your serving platter, then begin building the tower like a croquembouche, gluing the meringues together with dollops of whipped cream. Once you’re happy with the shape, bring it to the table and drizzle with the chocolate sauces (gently reheating them if needed).