Begin by boiling the potatoes in salted water until they are tender, which should take about 20-25 minutes.

Drain the potatoes well and set them aside to cool for a few minutes.

Once the potatoes are cool enough to handle, peel and mash them in a mixing bowl until smooth.

In the same bowl, integrate potato starch, a pinch of salt, and the egg if using. Mix gently until it forms a cohesive dough.

Shape the dough into 2-inch balls with your hands. Dust with more potato starch if too sticky.

In a large pot, bring salted water to a gentle simmer. Drop the dumplings into the water, ensuring space for them to move freely.

Cook until they float, taking about 10-15 minutes, which indicates they are done.