I found this on www.arborteas.com. During my study of Mandarin Chinese an instructor who originated from Xi'an had made these for us. I'm not sure if this is the same recipe but boy were they good; so savory and salty. In Guam, I had something similar at a Japanese ran noodle house. It was a boiled egg that had been cracked and cured in a soy sauce and tea mixture. The egg was completely brown but as we only live once I ate it and to my surprise it was a winner.
On www.arborteas.com, they give you a few fun ways to eat this delicacy. Check it out and enjoy.
Place the eggs in a medium-sized pot with enough cool water to cover by 1-inch. Bring the water to a boil, then lower heat to simmer for 3 minutes.
Remove the eggs with a slotted spoon and place in a bowl of cool water. Reserve the simmering water in the pot for use in the next step of the recipe. When cool enough to handle, take the back of a spoon and gently crack the eggs evenly all around the shell. Take care when cracking to leave the shell intact. This allows the dark steeping liquid to seep into the egg white, staining it with a marbled design. The more you crack, the more intricate the design will be.
Add the remaining ingredients to the pot of simmering water, stirring to combine. Return the cracked eggs to the pot as well. Bring the liquid to boil again, then reduce the heat to low and simmer for 40 minutes. Turn off the heat and cover the pot with a lid. Let the eggs steep for a few hours to overnight. The longer the eggs steep, the more intense the flavor and color will be.
Drain the eggs, peel and serve. Unpeeled eggs can be refrigerated in a covered container for up to 4 days.