Makes 12 
Easy
20 minutes
15 minutes Lightly grease a 30 x 11 x 7 cm loaf tin with oil and dust with the icing sugar and cornflour.
Combine the sugar, ¾ cup water and liquid glucose in a saucepan over a medium heat. Stir until the sugar has dissolved, then bring the syrup to the boil, without stirring.
Increase the heat and boil until the syrup reaches 127°C (hard ball stage).
Soak the gelatine in the remaining water for 5–10 minutes, then dissolve it very gently over a saucepan of boiling water or in the microwave for 20–30 seconds.
In an electric mixer, whisk the egg whites until stiff peaks form. When the sugar has reached 127°C*, pour in the melted gelatine, then immediately pour the syrup into the electric mixer in a slow, steady stream. Continue whisking until the mixture is a thick, white, opaque mass.
Spoon the marshmallow mixture into the prepared tin. Allow to set for a few hours.
Loosen the marshmallow from the tin using a palette knife. Dust a work surface with icing sugar and turn the marshmallow out onto it. Dust with more icing sugar and cut into squares. Allow to dry for 1 hour.
Just before serving, scorch the marshmallows using a blowtorch.
Cook's note: *No thermometer? No problem! Test a little sugar syrup by dropping it into cold water to see if it's ready.
Sugar goes through several stages as it boils: thread, soft ball, firm ball, hard ball, soft crack and hard crack. As the liquid boils away, the temperature increases and the concentration of sugar become greater. Each stage describe what its consistency will be when dropped into cold water.
Fudge needs the soft boil stage, while marshmallows are cooked to the hard-ball stage. Ideally, you should use both the cold-water test and a sugar thermometer for the most accurate result.
