Maple Syrup - 1/4 cup
Half Pints Stir Stick Stout - 1/4 cup
Butter, Cold, Cubes - 1/4 cup
Corn starch - 1 tbsp
Water, Cold - 2 tbsp
Mix the Stout and Maple Syrup in a small pan. Bring to a boil.
Reduce heat to simmer. Add the butter a little at a time, making sure to stir constantly until all of the butter is incorporated.
In a small bowl, mix the cold water and corn starch. Immediately add it to the simmering mixture. Increase the heat.
Bring to a boil stirring constantly. When it boils the corn starch will achieve its thickest. Turn off heat. Adjust texture with a little water or cream.