Start by trimming all the fat away from the outside of the beef. If you see a thick vein of fat running through the middle of the roast, follow this line and cut the fat out.
Slice the beef jerky into 1/8th inch (1/4 cm) thick strips with a sharp chefs knife or serrated slicer. You can place the raw beef in the freezer first for half an hour to firm it up prior to slicing, resulting in more even strips of beef.
Mix your seasonings in a bowl, and then sprinkle it over the sliced beef strips. Use your hands to mix it in well, and evenly distribute it. Cover and refrigerate for at least 2 hours, or ideally over night. I usually let my jerky sit for about a day before drying it.
Once you are ready to dry your jerky, pre heat your oven to 300F, and place tinfoil or a large sheet pan in the bottom to catch any drippings and prevent scorching. (See notes below on food safety). Thread the beef strips onto a wire hanger, or lay them out on a wire rack over a sheet pan.
Hang/Place the beef strips in the oven for about 10 minutes to get the meat to reach 160 F killing any bacteria prior to drying. Drop the temperature to between 130F / 55C and 140F / 60C to finish drying the beef. This can take anywhere from 4 to 8 hours depending on the temperature setting and the thickness of your beef jerky. If your lowest oven temperature setting is 170F / 77C wedge the door open with a wooden spoon to let heat escape and keep the temperature lower.
Once the beef jerky is dark, fully dried, and has a slight crack when bent, the jerky is done. Remove the homemade beef jerky from the oven and let it fully cool. Use paper towel to soak up any beads of fat that may have appeared.
Store the beef jerky in an airtight container for 3 to 4 weeks in a cool dry location, or vacuum seal it for an even longer shelf life. The jerky can easily be frozen or refrigerated to ensure no possibility of bacteria growth.