Melt butter in a medium saucepan.

Add sugars and stir to combine over low heat. Make it into an even layer in the pan and continue to heat on low until the mixture becomes fragrant and begins to bubble.

Add 1/2 cup of cream and whisk until combined on low/medium heat. The mixture may seize/harden for a minute but will end up melting/combine.

Add the last 1/2 cup of cream and stir until combined.

Heat on medium, whisking occasionally, until the mixture turns to a pale color and bubbles up to the top of the pan. Once bubbled up, continue to cook over medium heat for one minute and then turn off the heat.

Add sea salt and vanilla. Whisk until combined.

Pour into jar and refrigerate between uses.