In a large mixing bowl, whisk together the flour, dashi stock, and eggs until smooth.
Add the shredded cabbage, minced green onions, chopped squid, and small shrimp to the batter. Mix well to combine.
Heat a large non-stick pan or griddle over medium heat. Add a small amount of oil to coat the pan.
Pour about 1/4 of the batter onto the pan and spread it into a circle.
Cook for about 4-5 minutes, or until the bottom is golden brown and crispy. Flip the okonomiyaki and cook for an additional 4-5 minutes until cooked through.
Repeat with the remaining batter to make 4 pancakes.
Top each pancake with mayonnaise, okonomiyaki sauce, bonito flakes, and aonori seaweed flakes (optional).
Serve hot and enjoy!