01 - Grate half of the potatoes using the large holes of a box grater. Place the grated potatoes in a clean kitchen towel and squeeze out as much moisture as possible.
02 - Boil the remaining potatoes in salted water until tender, about 10 to 12 minutes. Drain well and mash until smooth.
03 - In a large bowl, combine the grated raw potatoes, mashed potatoes, flour, baking powder, salt, and pepper.
04 - Stir in the milk and melted butter until a thick batter forms.
05 - Heat the oil in a large non-stick skillet over medium heat.
06 - Drop heaping tablespoons of the batter into the skillet, flattening gently to form pancakes about ½ inch thick. Fry for 3 to 4 minutes per side, or until golden brown and crispy.
07 - Transfer cooked boxty to a paper towel-lined plate. Repeat with remaining batter, adding more oil as needed.
08 - Serve hot, topped with a dollop of sour cream and a sprinkle of chives or scallions.