For the dipping sauce: Combine all the dipping sauce ingredients in a bowl and let it sit while you make the pancakes. Remove the ginger and cilantro before serving.
For the pancakes: Put the egg, water, sesame oil, and salt into a blender and blend well. Add the flour and blend until smooth, it should be the consistency of heavy cream. Stir in the cilantro, scallion, and sesame seeds. Heat a large nonstick skillet over medium high heat; add 1 teaspoon peanut oil and spread it around the pan with a paper towel. Pour in half the batter, swirling and tipping the pan to get one thin layer over the bottom of the pan. Cook until set, about 2 minutes. Flip the pancake with a spatula and cook on the other side for about 1 minute. Place the scallion pancake on a platter and make another pancake with the remaining batter. Cut the pancakes into wedges or roll them up and cut them into pieces. Serve with the dipping sauce.