Start by preparing the soy dipping sauce:

1. In a small bowl, combine soy sauce, rice vinegar, toasted sesame oil, toasted sesame seeds, and optional chopped red pepper (seeds removed).
2. Stir and set aside.

Prepare the scallions:

1. Thoroughly rinse and remove the first outer layer of the scallions. Separate the white part from the green.
2. Cut the green parts into 2-inch (5 cm) pieces and set aside.
3. Cut the white pieces into 2-inch (5 cm) pieces, then lengthwise into ¼ inch (0.5 cm) stripes and set aside. 

Make the pancake batter:

1. In a bowl, add all-purpose flour, cornstarch, baking powder, garlic powder, salt and pepper. Whisk together until combined.
2. Add the iced water gradually while whisking dynamically to remove the lumps, until the batter reaches a crepe consistency.
3. Add the green onion stalks to the batter and mix until all the stalks are well coated (the batter should leave a thin film on the vegetables).

Cook the pancakes:

1. Heat 3 tablespoons (45 ml) of neutral oil vegetable oil in a non-stick pan, over medium heat.
2. Transfer 1 and ½ cups of batter to the pan, spreading it thinly, about ½ inch (1 cm) thick and 8 inches (20 cm) large.
3. Cook for 5-7 minutes on each side, or until golden brown on each side. Add 1 tablespoon (15 ml) of oil to the pan before flipping the pancake to cook the second side. 
4. It’s ready! Serve immediately with the soy dipping sauce and a chilled glass of Riesling.