Place the cornflakes into a small circle in the centre of a large plate and top with the ice cream.
Whisk the egg whites until stiff peaks are formed, then whisk in the sugar until stiff glossy peaks are formed again.
Spoon the egg white mixture into a piping bag and pipe over the ice cream.
Using a mini-blowtorch, heat the meringue until golden brown.
Spoon the mixed berries round the bottom of the baked Alaska and dust with icing sugar.
To make the coulis, place the mixed berries, lime juice and icing sugar into a small food processor and blend until smooth.
Pass the berry mixture through a fine sieve.
To serve, spoon two tablespoons of the coulis around the baked Alaska.