After cooking my beef broth for about 15 hours I let cool I the fridge and scrape the fat off ( storing it in a container to use for frying later .. just like you would use butter )
The cooking process continues … boiling or simmering on low ( all day for another 2 days this sane process happens until cooked for 48 hours )
remember to add water to the pot if the water level does not cover the bones!! You don’t want it to burn after all that waiting !!!!