Wash green onions and pat dry with paper towels. Trim off the roots, vertically split each stalk down the middle, and chop into 2-inch-long pieces. Transfer into a large mixing bowl.

Add the remaining batter ingredients to the mixing bowl and mix just until combined. Do not overmix.

Heat 2 ½ tablespoons vegetable oil in a large non-stick pan on medium-high heat. Swirl the oil in the pan and add the green onions from the batter first, spreading them evenly. Then scrape out and pour the remaining batter over to fill in any gaps. Reduce to medium heat and fry until the bottom is crispy, golden with some charring, about 4-5 minutes.

Flip the pancake over with a large spatula and pour remaining oil along the edges of the pan. Swirl the pancake around in the oil and occasionally press down on it.

Transfer the pancake to a cutting board and slice with a sharp knife into small pieces.

In a small bowl, combine the dipping sauce ingredients as listed above and serve with the pancake.