In a large saucepan (much larger than you would ever think you would need), heat white sugar over medium-low heat. You can swirl the pan slightly to mix the sugar as it is heating, but resist the temptation to stir the sugar mixture until you see the edges begin to melt.

Once you see the sugar beginning to melt, stir the sugar with a heat proof spatula or wooden spoon to aid in the melting process.

Watch constantly as the sugar is melting, stirring frequently to prevent burning. You will notice the sugar begin darken from a light gold.

As the sugar changes from dark gold to deep amber, it will begin to smoke.

Once the sugar starts to smoke, remove the pan from the heat.

Immediately, stir in the butter and heavy cream. The sugar will foam up and steam. (This is why you need a larger pan than you would initially think.) It will get a bit resistant to your stirring, but keep stirring to incorporate the butter and cream until the mixture becomes smooth.

Add vanilla, cinnamon, and salt. Stir to incorporate.

Let the caramel sauce cool slightly, stirring occasionally.

Taste the caramel. If it smells or tastes burnt, pitch the batch and start over. You may need to use a lower heat setting to slow the process down a bit.

Store caramel in a covered container in the refrigerator. It will last for two to three months.