Divide the potatoes in half. Chop half the potatoes into 1” (2.5cm) pieces. Use a box grater to grate the remaining potatoes.

Add to a large pot and fill with enough cold water to cover the potatoes by ½” (1.3cm). Cook the potatoes until they are fork tender, stirring occasionally, about 20 minutes.

While the potatoes cook, transfer the grated potatoes to a kitchen towel, gather the sides together, and squeeze out as much liquid as possible. Set aside.

Drain the potatoes completely, then add them back to the pot to ensure any remaining liquid evaporates. Add the potatoes to a large bowl and mash them with a potato masher or fork.

Add the raw grated potato, flour, egg, baking powder, salt and black pepper to the bowl. Mix until evenly combined, then add the buttermilk, little by little until you have a pancake-batter consistency.

Heat a large nonstick skillet over medium heat, add 1 tablespoon (14g) butter and allow to melt. Use a ¼ cup measuring cup to scoop the portions into the pan. Cook until crispy and golden brown on the bottom, about 4 minutes. Flip and continue to cook until crispy, adding additional butter if needed, about an additional 4 minutes. Lower the heat if they start to brown too fast.

Remove to a baking sheet and repeat with the remaining batter. Top the boxty with a spoonful of crème fraîche and smoked salmon. Garnish with chives and serve.