Bake the potatoes at 425 degrees until tender, about 1 hour. Cool slightly, then halve and scoop the flesh into a
ricer or food mill; press into a bowl. (You can also
mash well with a fork.)
Add the egg, cheese, butter, 1 teaspoon salt, and pepper to
taste; stir with a fork until combined. Add the flour and stir to make a rough dough, then mix by hand until smooth. Add more flour if it’s sticky.
Gather the dough into a ball on a floured surface and divide into 8 pieces. Roll each piece into a 12-inch-long,
1/2-inch-thick log with your hands.
Cut the logs into 1-inch pieces. Freeze on floured baking sheets until ready to cook. (Once frozen, store up to 1 month in a sealed container.)