Stir to combine the sugar and water in a medium heavy-bottomed saucepan, and set over medium-high heat. Do not allow the flames to lick the sides of the saucepan. Cook, stirring until the sugar dissolves, and the mixture becomes clear and starts to bubble along the edges.
The key here is that you are melting the sugar grains. You are safe to stir the sugar and water as much as you need to at this point, but if possible, try not to splash the sugar up onto the sides of the pan too much, as you’ll just have to wash them off in the next step.
Set a bowl of water next to your burner and wet a pastry brush in it. Then run the wet brush along the edge of the bubbling sugar mixture, brushing down any crystals of sugar. This is extremely important if you want smooth caramel sauce! Think of it as “washing” down the sides of the pot.
If you want to use a candy thermometer, now you can set a sugar thermometer on the side of the saucepan. It is important to set it so that the indicator is submerged into the simmering sugar. If your syrup is not deep enough to submerge the thermometer’s sensor, you can burn your caramel.
Let the sugar simmer over medium to medium-high, undisturbed. DO NOT STIR!
The timing for step three will vary depending on the size of your saucepan and how much water you used to brush down the sides. Be patient! It can seem stuck at 212 for a long time, and will go slow until all the water has evaporated. Then it will start to climb quickly once the water is cooked off.
That’s when you’ll start to see bigger and bigger bubbles and the mixture will darken. Gently swirl the pan and continue cooking until the mixture is 240 degrees F and amber colored. As a guide, note that this will take about 7 to 8 minutes, but your timing will vary depending on your conditions, equipment etc.
No Thermometer? No Problem! Visual cues go a long way for this sweet sauce.
A light blonde color will produce a mellow caramel flavor for the sweet sauce, while a deep amber color (longer/higher heat) will have a little more of a bitter taste.
The mixture will keep cooking and temp rise quickly, so once it starts to darken to golden brown, be ready to add the cream to prevent it from getting too dark.
Quickly remove the saucepan from the heat and carefully pour in the whipping cream and Bourbon. The mixture will bubble vigorously. Now it is okay to stir! Whisk in the salt. If the mixture is not smooth, return to medium heat, whisking until smooth, about 1 minute.
Transfer the caramel to a heat-proof jar and allow to cool. Use or store in the fridge for up to 2 weeks.