Place potatoes in a saucepan, cover with cold salted water. Bring to a boil, then simmer for 15-20 mins until very tender. Drain well, return to hot pan for 1 min to dry.

Mash potatoes in a bowl until completely smooth. While still hot, mix in softened butter and 1 tsp salt until butter melts.

Sift ¾ cup flour (and baking powder, if using) over potato mixture. Gently mix with a fork until a soft dough forms.

Turn dough onto a well-floured surface. Knead gently, adding flour a tablespoon at a time, until dough is smooth and no longer sticky (about 2-3 mins). Do not over-knead.

Pat or roll dough into a circle about ½-inch thick. Cut into 4 equal wedges with a floured knife.

Heat a skillet/griddle over medium-low. Add ½ tbsp butter. Cook farls for 4-5 mins per side until golden brown and crisp in spots. Add butter for each batch.

Transfer cooked farls to a wire rack. Serve immediately with plenty of butter.