Place one of the chicken pieces between two plastic sheets or in a large plastic bag, and do not seal. Flatten to an even thickness, about ½-inch thick. Repeat with the remaining pieces. Alternatively, for pieces 1-inch thick or larger, cut in half horizontally to create eight ½-inch thick pieces.

Use paper towels to pat dry both sides of the chicken to remove excess surface moisture.

In a small bowl, combine kosher salt, black pepper, paprika (if using), garlic powder, onion powder, and Italian seasoning (if using). Evenly sprinkle both sides of the chicken with the seasoning mix, about ¼ to ½ teaspoon per side.

Heat a large skillet over medium heat, then add the olive oil. Once hot and shimmering but not smoking, add the chicken presentation side down. Use tongs to press down into the pan for maximum contact. Cook until golden brown, about 5 to 7 minutes.

Flip the chicken over and add the butter. Swirl the pan to melt and evenly distribute. Occasionally baste the meat with the butter. Cook until the internal temperature reaches 160 to 165ºF (71 to 74ºC), about 5 to 7 minutes.

Rest the chicken on a clean plate or cutting board for 5 minutes. Serve whole pieces of chicken breast, or slice crosswise into strips or dice into cubes.