Bring a large pot of salted water to a boil. Peel potatoes and add to pot. Cook until tender but still firm, about 15 minutes. Drain, cool and mash with a fork or potato masher.

Combine 1 cup mashed potato, flour and egg in a large bowl. Knead until dough forms a ball. Transfer dough to a ziplok bag and snip off the tip.

Bring a large pot of lightly salted water to a boil. Squeeze out the dough in 1/2-inch long segments and snip off directly into the water. Cook for 3 to 5 minutes or until gnocchi have risen to the top; drain and serve.