Pat the beef brisket dry on all sides with paper towels to remove excess surface moisture, which helps the seasoning adhere and encourages browning in the air fryer.

Drizzle the brisket on all sides with the olive oil, rubbing it in with your hands to create a thin, even coating that will help the spice mixture cling to the meat.

In a small bowl, combine the kosher salt, freshly ground black pepper, garlic powder, onion powder, smoked paprika, dried thyme, dried oregano, ground cumin, brown sugar, and cayenne pepper if using, stirring until the mixture looks evenly blended.

Sprinkle the seasoning mixture generously over the oiled brisket, then massage it into every surface, including the sides, so the meat is well coated with the flavorful rub.

Let the seasoned brisket rest at room temperature for about 15 minutes to allow the spices to begin penetrating the surface while you prepare the air fryer.

Preheat your air fryer to 320°F (160°C) for 5 minutes so the basket is hot when the brisket goes in, which helps develop a flavorful crust.

Pour the low-sodium beef broth into the bottom of the air fryer drawer or under the basket if your model allows, making sure the brisket will not be sitting directly in the liquid but will benefit from the gentle moisture as it cooks.

Place the seasoned brisket into the preheated air fryer basket with the fat side facing up, arranging it in a single piece without folding so the hot air can circulate around it evenly.

Cook the brisket at 320°F (160°C) for 30 minutes, then carefully open the air fryer and use tongs to check that the rub is forming a light crust on the surface.

Flip the brisket over so the fat side is now facing down, then continue cooking at 320°F (160°C) for another 25 minutes to gradually render the fat and tenderize the meat.

After this time, flip the brisket once more so the fat side faces up again, then increase the air fryer temperature to 360°F (182°C) and cook for an additional 10 to 15 minutes to deepen the crust and finish cooking to your desired doneness.

Carefully remove the brisket from the air fryer and place it on a cutting board, tenting it loosely with foil, and let it rest for at least 10 to 15 minutes so the juices redistribute throughout the meat.

Slice the rested brisket against the grain into thin slices using a sharp knife, then arrange the slices on a serving platter and spoon any collected juices from the cutting board over the top before serving.