For Air Fryer: 

1. In a large bowl, stir together ground beef, 2 tablespoons barbecue sauce, salt, and black pepper. Shape mixture into 8 burgers, each ½-inch thick. (Even thickness ensures even cooking and prevents the edges from drying out before the center is cooked). 
2. In air fryer basket, arrange 4 burgers in a single layer.  
3. Set air fryer temperature on 350°F. Turning halfway through, cook 10 to 12 minutes, or until meat thermometer registers 160°F and burgers are no longer pink in center. 
4. Remove burgers from basket and keep warm. Repeat cooking with remaining burgers. 
5. Place each burger on a slider bun and top with ½ slice cheddar cheese, 1 ½ teaspoons barbecue sauce, and 1 tablespoon fried onions. 

For Air Fryer Toaster Oven: 

1. Preheat Toaster Oven on Air Fry to 400°F. 
2. In a large bowl, stir together ground beef, 2 tablespoons barbecue sauce, salt, and black pepper. Shape mixture into 8 burgers, each ½-inch thick. (Even thickness ensures even cooking and prevents the edges from drying out before the center is cooked). 
3. In air fryer basket, arrange burgers in a single layer. Place basket on bake/broil pan. 
4. Slide pan into upper rack position. Turning halfway through, cook 10 to 12 minutes or until meat thermometer registers 160°F and burgers are no longer pink in center. 
5. Place each burger on a slider bun and top with ½ slice cheddar cheese, 1 ½ teaspoons barbecue sauce, and 1 tablespoon fried onions. 

Serves: 4-8