Add everything but the beef into a gallon-size resealable plastic bag. Seal it and shake until the brown sugar fully dissolves.
Add the sliced beef to the marinade and toss it gently enough to coat all sides.
Refrigerate anywhere from 8 to 24 hours. The trick to making great jerky is that longer you marinate it, the more flavor and saltiness will make its way into each bite.
Remove the strips from the bag and transfer them to paper towels. Pat the meat dry.
Preheat your smoker to 170°F. Transfer the strips to the grill grate and season them with some extra black pepper if you like.
Smoke anywhere between 2-5 hours, depending on the thickness of your slices.
Make frequent checks during the first hour to ensure even drying. The ideal texture is firm with a bit of pliability, nothing outright soft. If the jerky breaks when bent, it is overcooked.
Store the jerky in a gallon-size bag while it is still warm, leaving only a small part of the band unzipped.
If you used the optional ingredient, your jerky will last for weeks without refrigeration. If you did not use the optional ingredient, the jerky will last several weeks with refrigeration.