1. Cut off the white end of the green onions and save for another recipe. Slice the green part thinly on a diagonal.
2. In a medium bowl, add the flour, salt, pepper, and garlic powder. Whisk to combine. Whisk in the ice water until the batter is similar to traditional pancake batter. (Not too thick and not too thin). Stir in the scallions and crab.
3. Add a thin layer of cooking oil to the bottom of a large (12-inch) non-stick saute pan. Heat the oil over medium-high heat until it is hot and shimmery. Ladle the batter to the pan for the pancakes (about 3 or so 4-inch pancakes per batch). Cook for about 3 or 4 minutes until the edges look dried and bottom has browned. Flip pancakes and cook for another 3 or 4 minutes or until browned. Add more cooking oil as needed.
4. Transfer the cooked pancakes to a cutting board. Repeat cooking with the remaining batter.
5. Cut the pancakes into bite-sized pieces. Serve at room temperature with dipping sauce.

For the dipping sauce:

1. Place all ingredients except toasted sesame seeds in a jar with a lid. Shake to combine. Pour into dipping bowl. Sprinkle toasted sesame seeds on top.