In a large bowl, mix together the ground beef, soy sauce, garlic powder, Kosher salt, and black pepper. Divide the ground beef into equal portions and form them into burger patties.
To prepare your Ninja Foodi, select the "Air Crisp" function and set the temperature to 400 degrees F. Preheat for 2-3 minutes.
Once the Ninja Foodi is preheated, place patties in the air frying basket, ensuring they are not overcrowded. Depending on the size of your Ninja Foodi, you may need to cook them in batches.
Close the Ninja Foodi lid and air-fry the patties for about 7-8 minutes, flipping halfway through. Cook until the patties reach your desired level of doneness and develop a golden-brown crust on the outside.
While the patties cook, prepare your burger buns and desired toppings. Once the patties are done, remove them from the Ninja Foodi and let them rest for a minute.
Place each cooked patty on a burger bun and add your favorite toppings.