Melt the butter in a small saucepan over low heat.
Stir in the flour and cook for 2-3 minutes until well combined and golden brown.
Whisk in ¼ cup of the beef broth, the mixture will become a very thick paste. Gradually whisk in ¼ cup more broth. Once the mixture has thinned slightly you can gradually whisk in the remaining broth.
Add the Worcestershire sauce, the beef base, and the pepper.
Bring to a boil then reduce to a low simmer and cook for 2-3 minutes until thickened and glossy.
Add the heavy cream, taste and season with salt if needed.
