To make the soy dipping sauce, combine soy sauce, rice vinegar and sesame oil in a small bowl. Set aside.
In a large bowl, sift together the flour, cornstarch and salt. Whisk the egg with the water, and then add the egg mixture to the flour mixture.
Add the shallots, garlic chive, zucchini, onion, red chilli, prawn and squid.
In a non-stick pan, heat 1 tablespoon of the oil until hot.
Spread the mixture, thinly covering the whole pan and cook over high heat for about 3 minutes or until the bottom is crisp and browned. Carefully flip the pancake and cook other side for about 1 minute or until set.
Cut into slices and serve the pancake with soy dipping sauce.
This dish is normally eaten with Korea's traditional rice-based wine.