Beer Syrup

2 (12 fluid ounce) bottles any flavor beer, preferably not light beer

1 tablespoon butter

Heat the beer in a saucepan over medium-high heat, stirring constantly, until it comes to a boil; allow to boil until the beer thickens to almost the consistency of a glaze, about 15 minutes. Stir the butter into the beer until the butter melts. Use immediately.