Off the heat, blend beaten egg into hot butter mixture.
Return to heat; bring to a boil over low heat, stirring constantly. Cook 1 to 2 minutes or until thickened enough to coat the back of a spoon. Do not allow the mixture to simmer as the sauce will curdle. The Bourbon Butter Sauce should be soft, creamy, and smooth.
Remove from heat and serve warm.
NOTE: If made in advance, whisk and reheat before serving.
Makes enough for 6 servings.
* Use a good-quality bourbon.
Bourbon Butter Sauce Recipe: https://whatscookingamerica.net/sauces_condiments/bourbonbuttersauce.htm