Moloko Butterscotch

In a large, heavy-bottomed saucepan, melt both sugars and butter over medium heat; do not boil. Meanwhile, in another small saucepan, heat heavy cream until hot.

When sugars and butter have melted, add cream, 1/3 cup at a time, cooking for 30 seconds after each addition. Add salt and vanilla; stir to combine. Add stout and stir to combine. Bring to a boil and cook for 30 seconds. Remove from heat and let cool.