Caramelize the onions in a small amount of olive oil. Add garlic and cook for a minute or two more.
Deglaze the pot with white wine, then add Worcestershire sauce and cook for another minute, stirring constantly.
Add beef broth and bring to a light boil. Reduce heat and simmer for about 3 minutes.
Strain broth and then return it to pot. Add flour and simmer an additional 5 minutes.
Serve with French Dips and ENJOY!
Video
Notes
If you want a gluten free version, you can use corn starch or tapioca starch instead of flour. Create a slurry with cold water and a small amount of the starch before pouring it in – this will prevent clumping.