In a medium saucepan, add sugar, salt, glucose and water.
Heat slowly till the sugar is dissolved.
Bring to the boil and boil to the soft ball stage (118°C)
Beat egg white to stiff peak
Stir the gelatin into the boiled sugar
Pour the syrup into the egg white, beating continuously until the mixture becomes thick and creamy.
Beat the vanilla extract and colouring in with a wooden spoon.
Sift 100ml of icing sugar and 50ml of corn flour and sift a layer over the base of a 20cmx20cm baking tin
Pour the marshmallow into the tin and top with remaining sifted icing sugar mix.
Leave to set firm
Turn out onto a cutting board, cut into squares and dust the cut sides with more icing sugar.