Start by peeling and chopping the boiled potatoes into even pieces. Place them in a large pot of salted water and bring to a boil over high heat. Cook for 15-20 minutes, or until fork-tender. Drain well in a colander.

While the potatoes are still warm, mash them using a potato ricer or masher until smooth and lump-free.

Stir in the unsalted butter and salt into the warm mashed potatoes, allowing the butter to melt. Gradually mix in the all-purpose flour until a soft dough forms.

On a lightly floured surface, turn out the dough and gently knead it for about 1-2 minutes until smooth and cohesive. Divide the dough into two equal portions and roll each piece out to 1/3 inch thickness.

Cut each rolled-out round into quarters, creating 8 wedge-shaped pieces.

Heat a cast-iron skillet over medium-high heat. Place each wedge into the dry skillet, cooking for 3-4 minutes on each side until golden brown and crispy.

Transfer the warm wedges to a plate lined with a kitchen towel to keep them warm. Serve immediately.