Slice chicken breasts in half lengthwise for thinner pieces. Pound with a meat tenderizer to ¼-½ inch thick for even cooking.
Mix salt, black pepper, garlic powder, onion powder, and paprika in a bowl. Coat both sides of the chicken evenly.
Heat 2 tbsp butter in a cast-iron skillet over medium heat. Add chicken and cook for 4-5 minutes per side, until golden brown and cooked through (internal temp 165°F).
Add 1 tbsp butter in the last minute, spooning it over the chicken.
Let rest for 3-5 minutes before slicing.