Cut the beef into strips about 4cm thick. Pack the meat into a smallish bowl, so that it fits tightly.
Add the vinegar and Worcestershire sauce. Leave for 30 minutes.
Meanwhile, mix the coriander and pepper together in another bowl.
In a third bowl, mix the salt, sugar and bicarbonate of soda together.
Remove the meat from the marinade, but reserve the marinade for later use.
Add the beef to the bowl of spices, mixing it around until evenly coated. Save any spices that don't stick.
Bury the spiced beef in the salt and the sugar mixture and leave it for 3 hours.
Remove the beef from the brine and dip it back into the reserved vinegar marinade for another 5 minutes.
Remove the beef from the marinade and using the vinegar, wash all the salt off (don't skip this bit or the biltong will be unbearably salty).
Squeeze the beef to remove as much liquid as possible. Roll in the spices once more. The meat is now ready for hanging.
Cut lengths of string, and tie them tightly around one end of each beef strip. Tie the string to the top of your hanging contraption and make sure that they hang freely without touching anything on the sides or bottom.
Leave the strips hanging for 3-20 days in a warm, dry place. It is difficult to say exactly how long it will take for the biltong to reach the correct stage, it's basically when the meat is as tough as old boots!