As it cools it will thicken.
Brooke's Note * If you plan to use it straight away, you are done.
I have found, though, if I plan to keep it in the fridge and use it later, it needs some xanthan gum to stop it from separating. After step 6 sprinkle about 1/4 tsp of XG from a salt shaker and whisk the sauce like crazy until it is dissolved. This will stop it from separating later in the fridge. When you are ready to use it just warm it for 10 seconds in the microwave to reach a pourable consistency.
Recipe by Nana's Little Kitchen at https://www.nanaslittlekitchen.com/brookes-five-minute-caramel-sauce/