500 grams Granulated Sugar
500 grams Demerara sugar
150 grams butter
small tin 218 grams Nestles sweetened full cream condensed milk
200 ml fresh whole milk
(I have recently discovered that Nestles seem to have stopped selling small tins of condensed milk and I adjusted my recipe the last time I made it with using the larger tin of condensed milk which is 397 grams and adding 200ml of water instead of fresh whole milk. The end result was the same.)
Add sugars with milk in a good sized heavy bottomed saucepan making sure the mixture has room to more than double in volume without boiling over and stir briskly until blended. Add butter and place on a low heat until the butter is melted and stir occasionally with a wooden spoon until until the sugar is melted and the mixture becomes smooth and starts to boil. Remove from the heat and stir in the condensed milk and return to the heat and bring the mixture back to boiling. Allow to boil for exactly 12 minutes stirring occasionally to prevent catching. Remove from the heat and stir briskly until the mixture begins to grain. This will take a few minutes and be good exercise for your wrists and biceps. As soon as you feel the grains of sugar forming turn it out quickly to a suitable flat swiss roll tin which has been lightly buttered. Leave to cool for a few seconds and score the surface lightly into squares with a sharp knife. Leave in a safe place until cold before turning out and breaking up into squares.
Some people prefer to add a few drops of vanilla essence at the end of the boiling period but I prefer the butter to be the main flavour and would always use a good quality unsalted butter. It is also very nice to have scattered your buttered tray with crushed hazelnuts before pouring.
It must be stressed that boiling sugars is a very dangerous practice and extreme care should be taken at all stages to avoid any splashing of such mixtures, it is still very hot when off the boil and will cause severe burns if coming in contact with the skin. Never be tempted to taste these mixtures whilst cooking or pouring as they will burn you as sugars boil at much higher temperatures than water and take much longer to cool. It goes without saying that the children will love the end result but should not be allowed near the kitchen when boiling sugars.