Gather all ingredients.

Cover potatoes with water in a pot and bring to a boil over high heat. Simmer on medium-high heat until center of potatoes are tender when pricked with a fork, about 20 minutes. Turn off heat. Drain, return potatoes to the pot, and allow to completely dry out over the remaining residual heat.

Mash with a potato masher until smooth.

Place warm mashed potato in a medium bowl. Stir in flour, melted butter, and salt. Mix lightly until dough forms.

Knead dough lightly on a well-floured surface. The dough will be sticky. Use a floured rolling pin to flatten into a 9-inch circle about ¼ inch thick. Cut into quarters using a floured knife.

Sprinkle a little flour into the bottom of a skillet and cook farls until evenly browned, about 3 minutes on each side. Season with a little salt and serve straight away.