Season the 4 Cube Steaks with 1 teaspoon Kosher Salt .
In a shallow dish, mix the 2 Cups All-Purpose Flour , 2 Teaspoons Kosher Salt , 2 Teaspoons Garlic Powder , 1 Teaspoon Smoked Paprika , and ½ Teaspoon Cayenne Pepper .
In another shallow dish, whisk together the beaten 2 large Eggs and 1 Cup Buttermilk .
Dredge each steak in the seasoned flour mixture, coating evenly.
Dip the floured steak into the buttermilk mixture, then return it to the flour for a second coating.
Place the breaded steaks on a wire rack and let them rest 10 minutes to set the coating.
Preheat the air fryer to 400°F (200°C).
Lightly spray the basket with cooking spray and place the breaded steaks inside in a single layer.
Air fry for 10–12 minutes, flipping halfway through, until golden brown and crispy.
In a small skillet, melt the 1 Tablespoon Butter over medium heat, scraping up any browned bits.
Whisk in the ¼ Cup All-Purpose Flour and cook 1–2 minutes to form a roux.
Gradually add the 2 Cups Whole Milk , whisking constantly until thickened.
Season with Salt and Freshly Ground Black Pepper to Taste to taste.
Place the air-fried steaks on plates and generously pour the creamy gravy over the top.