In a small saucepan warm the cream and condensed milk over a low heat. Once just warm remove from heat and keep warm.
In a medium saucepan place corn syrup, caster sugar and water. Heat over a high heat, stirring until all the sugar has dissolved. Once sugar has dissolved stop stirring and place a candy thermometer into your mixture. Bring the sugar syrup to the boil and continue to boil until it reaches 120 degrees C.
Take off the heat and add your cream mixture and butter. Mix well and place back on the heat. Stir continuously until the mixtures reached 120 degrees C again.
Once caramel comes to temperature, remove from heat and stir through sesame seeds. Pour into a well greased and lined 18 x 28cm slice tin. Bang the tin down on the kitchen bench a few times to help any trapped air bubbles escape.
Leave to completely cool on the kitchen bench (do not put in the fridge). Once completely cool, remove from tin and cut into desired sized pieces. Wrap individual caramel pieces in cut to size baking/greaseproof paper.
Makes 40 – 50 pieces depending on the size you cut them into.