Peel half the potatoes and dice them (1-inch/2.5cm). Boil them until tender (about 15 minutes), drain them and mash them (you should have about 1¾ cups/350gms).

While half the potatoes are boiling, prepare the other half. Peel them and shred them on the large holes of a box grater (you should have about 2 cups, packed/400gms).

In a large bowl, combine the mashed cooked potatoes, raw shredded potatoes, salt, baking soda, flour and buttermilk. Stir until well combined - you should have a soft cake-like batter. If using the green onions, you can add them into the batter or sprinkle them on top at serving time.

Heat one teaspoon of butter in a non-stick skillet over medium heat. Drop heaping tablespoons of batter into the hot pan and spread them out with the back of a spoon until they are pencil-thick and about 3 inches wide. Fry them for about 3 to 4 minutes until medium brown - low & slow is better since you want the raw potatoes inside to cook without the outsides getting too dark. Adjust the heat if necessary. Flip the boxty cakes and press down on them lightly with a spatula. Cook the second sides for another 3 to 4 minutes, adding more butter if needed. Remove them to a plate to keep warm while you fry up the rest.

Serve as a starchy potato side dish to a main meal or as a part of a cooked Irish breakfast with eggs and bacon or sausages, sprinkled with green onions.

Makes about 28 (3-inch) boxty cakes.