Begin by cutting the top sirloin steak into 1-inch cubes. Make sure the pieces are uniform in size for even cooking.
In a mixing bowl, combine the minced garlic, salt, black pepper, olive oil, Worcestershire sauce, and smoked paprika. Whisk together until well combined.
Add the steak cubes to the marinade, ensuring each piece is well-coated. Allow the steak to marinate for at least 10 minutes. For even deeper flavor, marinate for up to 30 minutes.
Preheat your air fryer to 400°F (200°C) for about 5 minutes. This step is crucial as it helps achieve that lovely crispy texture.
Place the marinated steak cubes in a single layer in the air fryer basket. Avoid overcrowding to ensure even cooking. Cook for 8-10 minutes, shaking the basket halfway through to promote even browning.
After 8 minutes, check the steak bites for doneness. They should be cooked to your desired level—medium-rare is typically around 130°F (54°C). Adjust cooking time as necessary.
Remove the steak bites from the air fryer and transfer them to a serving platter. Garnish with red pepper flakes and chopped fresh parsley for a pop of color and flavor. Serve immediately and enjoy!