Peel potato and grate on a large cut-box grater or grate in processor.
Rinse potato in cold water and squeeze dry.
Whisk egg in a bowl. Mix egg, potato, onion, parsley, matzah meal or flour, salt, and pepper.
In a sauce pan, heat oil and spoon in latkes to your desired size. Sauté until golden brown, turning once.
Remove from pan, draining latkes on paper grocery bag covered with a paper towel to absorb excess oil. Serves 4.