In a mixing bowl, whisk together the flour, water, and salt until smooth. Let the batter rest for about 10 minutes.
Heat a non-stick skillet or crepe pan over medium heat and lightly grease it with sesame oil.
Pour about ½ cup of the batter into the pan, swirling it to create a thin layer. Cook for 1-2 minutes until the edges start to lift and the surface is set.
Crack an egg on top of the crepe and gently spread it over the surface. Sprinkle with chopped green onions and any additional fillings like chicken or tofu.
Drizzle soy sauce and hoisin sauce over the top. Cook for another 1-2 minutes until the egg is cooked through.
Carefully fold the crepe in half and then in half again to form a triangle. Slide it onto a plate.
Repeat with the remaining batter and fillings. Serve warm with chili sauce on the side, if desired.