Place the sliced beef in a large mixing bowl. Add the coconut aminos, Worcestershire sauce (if using), all the spices, and the Besti Brown to the bowl. Mix well and refrigerate for at least 30 minutes or overnight, up to 24 hours.
Meanwhile, preheat the oven to 175 F (79 degrees C). Line a large baking sheet with foil and place an oven-safe non-stick cooling rack on top (I love this set which includes both).
Arranged the beef strips in a single layer on the wire rack.
Bake keto beef jerky for 3-4 hours, until it's dry and firm but still pliable, flipping the beef halfway through.
Cool completely. Store in an air tight container.