Split the shell in half crosswise and gently pour out the egg white into an airtight container. Separate the eggs and pour the yolks back into the shell. Add a teaspoon of soy sauce and swirl gently so that the soy sauce runs under the yolk. Stand the shell with the yolk up in the egg carton. Repeat with 5 more eggs.
Close the egg carton top and refrigerate for 2 to 3 hours to allow the yolks to cure.