450g castor sugar (superfine sugar)
200g pack of sesame seeds
Put the sugar and water into a pan on medium heat. Use a spoon to stir together - it will become a syrup.
Carry on cooking until light golden, then add sesame seeds, and continue to cook until dark golden.
Pour out onto an oiled non-stick tray or oiled tin-foil.
Use a palette knife to push it out to about 0.5cm thick (even thinner if you can).
Allow to cool for about 15 minutes, and you will have one big sesame seed caramel biscuit.