8 Tbsp unsalted butter
1 C brown sugar, packed
2/3 C heavy cream
1 Tbsp rum
1/2 tsp lemon juice
In a medium saucepan, over medium heat, melt the butter.
Whisk in brown sugar until smooth.
Continue to cook, stirring occasionally, until dissolved and puffy.
Slowly pour in cream and rum.
Whisk to combine.
Reduce heat and simmer until frothy.
Remove from heat and stir in lemon juice.