Preheat oven to lowest setting.
Whisk the egg whites until they reach the soft peaks stage, then add the sugar gradually and continue to whisk until stiff. Spread or pipe onto a foil-lined baking sheet in a round shape with raised edges (like a pavlova) and bake for 2 - 3 hours until dried out and very palely golden.
Mix the cornflour, sugar and a little of the evaporated milk to form a paste. Bring the remaining milk to the boil and whisk into sugar mix.
Return mixture to the pan and heat until thick, constantly stirring. Remove from heat and beat in egg yolks and vanilla. Allow to cool.
When ready to serve, spread the filling onto the meringue base and top with your chosen berries.
