Mix the ingredients. Place the roast drippings, cornstarch, butter, salt, pepper, broth, and Worcestershire sauce into a medium saucepan and whisk together. It's ok if it's not mixed well, the ingredients will melt and mix together when placed on heat.
Cook over medium-low heat until the butter melts, stir continuously. This should take about 5 minutes.
Thicken. Allow the mixture to come to a simmer over medium heat and cook while stirring until the gravy thickens to your liking. About 2 minutes.