Chocolate and hazelnut meringue cake

Prehat oven to 180 °C.
Grease and line the base of a springform pan, sprinkle with flour and tap out excess.
Toast hazelnuts until fragrant and skins start to crack (10 to 15 minutes).
Remove from oven and rub vigorously with a clean kitchen towel to remove skins.
Let cool, then chop roughly and set aside.
To make cake batter:
Cream butter and light brown sugar until pale and smooth.
Add egg yolks one at a time, beating well after each addition, until mixture is light and fluffy.
Add melted chocolate, vanilla and rum and beat until combined.
Set aside.
Combine egg whites and salt, and beat until soft peaks form (about 2 minutes).
Stir one third of the egg whites into the chocolate mixture.
Fold in remaining egg whites until just combined.
Pour batter into preapred and bake for 25 minutes.
To make meringue
Combine hazelnuts, chopped chocolate and cornflour in a small bowl and set aside.
Place remaining egg whites and cream of tartar in a bowl and beat until frothy.
Add sugar and beat until stiff peaks form.
Fold in hazelnut mixture.
Remove cake from oven.
Using a spatula, spread meringue mixture over it, then return cake to oven.
Bake until meringue is lightly brown and crisp (25 to 30 minutes).
Allow cake to stand for 10 minutes.
Run a knife around the edge of the cake to loosen, and release sides of the pan.
Let cool for about 30 minutes before slicing.