In a small saucepan over medium heat, melt the butter.

Stir in the brown sugar until combined. It won't fully combine.

Add the cream and mix until fully combined, and continue stirring until the mixture comes to a boil. Continue boiling and stirring until it thickens enough to coat the back of a spoon, about 2-5 minutes.

Turn off the heat, remove the pan from the burner, and add the maple syrup and salt (start off with 1/8 teaspoon and add more to taste).

Stir until completely incorporated and the salt has dissolved.

Use immediately or let cool completely before covering and refrigerating.

Refrigerate for up to 1 week. Before serving, stir to reincorporate the maple syrup and reheat in the microwave at half power for 10-15 seconds or until warm enough for your liking.