In a medium bowl mix together the flour, water, and salt until smooth with no lumps. The batter should be very thin consistency. Set the batter aside and let the mixture rest for 30 minutes.
Next, prepare the filling ingredients. Start by thinly slicing the green onions, then beat the eggs in a small mixing bowl, and set both aside.
Warm a large non-stick pan on medium heat and lightly brush with vegetable oil.
Pour 1/4 cup of the batter on to the pan and swirl around until the bottom on the pan is evenly coated. Cook for about 2 minutes then flip and cook the other side making sure that the pancake is lightly browned. Remove and set aside.
Then pour in the beaten egg and swirl the pan until there is an even layer of egg. While the egg is still wet generously sprinkle green onion and place the pancake on top. Make sure to press the pancake into the egg so that it sticks together and cook for another minute.
When the egg is fully cooked flip it and carefully roll the pancake so that the egg is on the inside.
Slice into bite sized pieces and serve with soy sauce!