Preheat the air fryer to 400°F (200°C).
In a mixing bowl, combine the cubed sirloin steak with paprika, salt, and black pepper. Toss to coat evenly.
In a separate bowl, mix the halved baby potatoes with 2 tablespoons of melted butter and season them with salt and pepper.
Place the seasoned steak bites in the air fryer basket in a single layer. Cook for 8 minutes, shaking the basket halfway through.
Remove the steak bites and set them aside.
Add the seasoned potatoes to the air fryer basket and cook for 10 minutes, shaking the basket halfway through.
While the potatoes are cooking, melt the remaining 2 tablespoons of butter in a small pan over low heat. Add the minced garlic and sauté for about 1-2 minutes until fragrant.
Once the potatoes are done, add the steak bites back to the air fryer and drizzle the garlic butter over the top. Cook for an additional 2-3 minutes to bring everything together.
Remove from the air fryer, garnish with fresh parsley, and serve hot.