Melt the sugar in a 2-3 quart saucepan over medium-high heat. You can really let it be until the sugar starts to melt. Then, stir to incorporate.

Once the sugar is completely melted, watch the caramel like a hawk, stirring occasionally. When the color turns golden to amber (the darker the color, the richer the flavor) add the butter all at once. Whisk like crazy until the butter is all melted.

Remove the pan from the heat and add your cream. It will bubble up like a mad science experiment so be prepared. Whisk until all of the cream has incorporated.

Whisk in your sea salt and set the pan aside to cool for 15 minutes. Then, pour the sauce into your glass jars to cool completely.

Serve the sauce at room temperature. Or it can be refrigerated for up to 2 weeks. Reheat by placing the glass jar in a saucepan of warm water or in 5 second intervals in the microwave.