Combine 7 cups water, the soy sauce, chili oil, tea leaves, five-spice powder, 2 teaspoons salt and the sugar in a medium pot over high heat. Bring the mixture to a boil, then reduce the heat to a simmer. Cover and simmer for 10 minutes. Turn off the heat, uncover and let cool completely.
Meanwhile, bring a large pot of water to a boil. Gently add the eggs and cook for 7 minutes. Remove the eggs and transfer to a bowl of ice water; let stand until cool to the touch.
Once the eggs have cooled, lightly crack the shells all over. The goal here is to make enough cracks to allow the flavor of the soy sauce mixture to steep into the egg. (You can also put them on a kitchen towel and roll gently.) Add the cracked eggs to the soy sauce mixture, making sure they are completely submerged. Refrigerate for 24 hours.
Peel the eggs. Cut a small piece off the wide bottom of each egg so it will sit flat, then cut off the top. Scoop out the egg yolks into a small bowl and mash them up with a fork. Stir in the mayonnaise, mustard, Sriracha, a pinch of salt and a few grinds of pepper. Tint orange with food coloring.
Pipe or scoop the filling into the egg whites. Sprinkle with black sesame seeds. Refrigerate until ready to serve.