In a mixing bowl, combine all-purpose flour and water, stirring until the mixture is smooth and thick. Allow the batter to rest for about 5 minutes.

Finely chop the spring onions and fold them gently into the batter along with the gochugaru.

In a non-stick frying pan, heat neutral oil over medium heat for 2-3 minutes until hot but not smoking.

Pour the pancake batter into the hot pan, spreading it evenly. Cook for about 5 minutes until the edges are crispy and the bottom is golden brown.

Flip the pancake gently and cook the other side for an additional 5 minutes until golden brown and crispy.

Remove the pancake from the pan, let it cool slightly, then slice into wedges or squares.

In a small bowl, combine soy sauce and vinegar. Whisk until well blended.

Serve the pancakes warm with the dipping sauce on the side.