Rinse dried beef and pat dry. Chop finely, I use a pizza cutter to make it faster. Reserve 1/4 c. of the dried beef.
Mix together cream cheese, sour cream, parmesan cheese, horseradish (you can use more than a tsp. if you like, I usually use 2 or 3 tsp.) and the 1/4 c. of dried beef.
When the ingredients are well mixed, form into a ball shape and set in the fridge to harden up. When the cheeseball is almost set, roll in the remaining dried chopped beef. Put back in the fridge to set the rest of the way.