In a small bowl, sprinkle the gelatine over 40ml of water (A) and set aside
In a small saucepan over medium heat, stir the 45ml of water (B) caster sugar and glucose syrup until the sugar is dissolved
Increase the heat to med-high and bring to a boil.
Simmer syrup for 5-8 minutes, until it reaches 128° on a candy thermometer
While syrup is simmering, begin to whisk egg white...
Whisking the egg white: In the bowl of stand mixer, whisk the egg white with a hand held mixer until soft peaks form (this is because 1 egg white is too small a volume, but you will need to use a stand mixer when adding the syrup). Attach the whisk to stand mixer
When sugar syrup reaches 128° remove from the heat and add the gelatine water mixture to the syrup (it will foam up)
Add syrup to the egg white (with the mixer on low) in a thin, steady stream
Continue to whisk the marshmallow for 15 minutes, until cool
Pour marshmallow over the caramel layer and allow to set (about 30 mins)