1. For this you need the right saucepan – my own favorite is a heavy-gauge aluminum one that is quite pale in color so that you can easily see the contrast between the color of the metal and the darkening color of the caramel.
2. This quantity makes enough caramel for a crème caramel to serve four to six people, or for six crème brûlées. Warm the pan gently over a medium heat for a few moments then place white caster sugar in the pan, still over a medium heat. Usually I recommend golden sugars but, in this instance, it's better to use white, as it is easier to see the change in colour. Leave the sugar like that, keeping an eye on it, until it begins to melt.
3. After about 5 minutes the sugar will start to melt and turn liquid around the edges. Now give the pan a good shake and leave it again until about a quarter of the sugar has melted.
4. Now, using a wooden spoon, give it a gentle stir and continue to cook and stir until the sugar has transformed from crystals to liquid and is the color of dark runny honey – a dark amber color. The whole thing should take about 10 minutes from start to finish and it is important to be patient and not try to rush it – this is where most people go wrong with making caramel. You must allow the full amount of time at a medium heat.
5. Then take the pan off the heat and add 2 tablespoons of tap-hot water – the caramel will splutter and steam so protect your hands with a cloth and take care. Stir well – you may need to return the pan to a gentle heat to re-melt any lumps of caramel that have formed. The caramel is now ready to use.