Start by preparing the marinade. In a large bowl, mix together the soy sauce, Worcestershire sauce, onion powder, garlic powder, ground ginger, and Chinese five-spice powder.
Thinly slice beef brisket into 1/4" thickness slices. It's easier to slice when the meat is partially frozen so you can put it in the freezer for 30-60 minutes prior to this step.
Add the thinly sliced beef brisket to the marinade, making sure that each piece is evenly coated. Cover the bowl with plastic wrap and marinate the meat in the refrigerator overnight.
The next day, remove the brisket from the marinade and use paper towels to pat each slice dry.
Preheat your pellet smoker to 160-180°F or as low as it can go. Place the brisket slices directly on the smoker grates. Be sure to leave a little bit of space between each slice so that the smoke can circulate freely.
Smoke the brisket for 3-4 hours, or until it reaches your desired level of doneness. The jerky should be dry and chewy, but not hard.
Once the jerky is done, remove it from the smoker and let it cool for a few minutes. Serve immediately or store it in an airtight container for later.