Preheat the oven to 200C/180C Fan/Gas 6. Line a 6 hole muffin tin with liners.
In a large bowl, or the bowl of a stand mixer, combine the butter and sugar for 3-5 minutes on high, until light and fluffy.
Add in the eggs, one at a time, mixing in between, and the vanilla extract.
Gently fold in the flour and cocoa powder until just combined. Add in the milk to loosen the batter a little.
Scoop the batter into the lined muffin tray. They should be about 2/3rds full. Bake for 18-20 minutes, until a skewer inserted comes out clean. Let cool on a wire rack.
Once cooled, poke holes into the top of each cupcake with a piping nozzle, to remove the 'core' of the cupcake.
Melt the Nutella in the microwave for 20 seconds (to loosen it), then drizzle it into the holes.
Preheat the oven to 220C/200C Fan (unless using a blowtorch).
Make the meringue by whisking the egg whites on high for several minutes, until soft peaks form. Add in the sugar, 1 tbsp at a time whilst still whisking. Do this until all sugar is combined and stiff peaks begin to form.
Scoop this mixture into a piping bag fitted with a large, round nozzle. Pipe the meringue over the cupcakes. Bake for 3-5 minutes, or torch with a kitchen blowtorch. Let cool slightly, then serve!
