This is the family recipe
1 tin condensed milk
500g sugar
2 tbsp golden syrup
10 g butter
1/4 cup hot water
Put all in a saucepan with high sides and boil on 3-4 on the induction hotplate stirring regularly. Watch the temperature and the colour. As it starts to brown keep a careful check on temperature. I aim for 121 deg C with the IR thermometer which in confectionery terms is the top end of "firm ball". Once it hits this temp turn off the heat and hit it with the electric beaters for a minute or so to promote nucleation of the supersaturated sugar solution. You are trying to produce a fine - not grainy - fondant so the more and the smaller the crystals the better. Then quickly pour into a 20cmx30cm tin lined with baking paper. Before it cools too much mark it into squares. If you don't it will shatter as you try and break it once it has cooled