Start by cutting your steak into evenly-sized bite pieces. Place them into a medium bowl and drizzle with olive or avocado oil. Sprinkle salt and pepper over the meat, then toss until each piece is coated well. This step helps ensure the seasoning sticks to the steak and allows the air fryer to crisp the edges.
Preheat your air fryer to 400°F. If your air fryer doesn’t have a preheat setting, just run it for 3 minutes before adding the steak. Once hot, add the steak bites in a single layer (avoid overcrowding) and cook for 4 minutes. Open and check for doneness. If you prefer a more cooked interior, continue in 1-minute intervals.
While the steak cooks, place the butter in a small skillet over medium heat. Once melted, stir in the minced garlic and cook for about 30 seconds. Be sure to stir constantly — garlic burns fast! Once fragrant and lightly golden, remove from heat and set aside.
Remove the steak bites from the air fryer once they’re cooked to your liking. Immediately toss them in the warm garlic butter sauce so they soak up all that flavor. Finish by garnishing with chopped parsley or chives if desired. Serve hot and enjoy!