Preheat the oven to 350°F/180°C, and line a sheet pan with foil or parchment paper. Preheat a cast iron pan as you prep the chicken: slice the chicken breasts lengthwise into halves, and pound them to an even thickness.
Make the seasoning mix, in a small bowl combine the paprika with garlic powder, onion powder, thyme, oregano, white pepper, black pepper, cayenne, and salt. Set aside.
Using a pastry brush, brush the chicken cutlets with melted butter on both sides, then generously season them with the seasoning mix, and transfer them to the prepared sheet pan.
When the cast iron pan is screaming hot, add the remaining butter, then lay the chicken. Cook for 1 minute on each side. Then transfer to the 2nd clean prepared sheet pan.