If using a larger roast, such as one closer to 3 pounds, just use heaping amounts of spices to create the rub. Note that the recipe requires a day of marinating prior to baking. After cooking, the dried meat is stored at room temperature.
Slice the beef against the grain into chunks roughly 1 inch by 3 inches long. If the pieces look large, that's fine; they'll shrink a lot as they cook.
In a mixing bowl, combine all of the spices. Liberally cover the beef pieces, using the entire mix. Place beef in a gallon bag, and keep sealed in the fridge for 24 hours or so.
Preheat oven at 250-degrees. Line a baking sheet with foil and place a metal rack on top; apply nonstick spray. Set the meat on the rack so that no pieces are touching.
Bake for 6 to 7 hours, until quite dry. If you want pieces chewier, remove closer to 6 hour point.
Let cool completely to finish drying. Store in sealed container at room temperature for up to several months.
OM NOM NOM!