Chop green onions into small pieces and mince pickled ginger.

Cut boiled octopus into 1cm cubes.

Mix water, egg, and dashi powder in a bowl. Gradually add rice flour and stir until smooth.

Preheat takoyaki pan and lightly grease with 1 tsp salad oil. Pour batter halfway into each mold, add octopus pieces, then fill molds to the brim. Sprinkle green onion, pickled ginger, and tempura flakes.

Cook for 3 minutes until edges solidify. Use skewers to rotate the batter into balls, pushing excess batter inside. Continue rolling until evenly browned.

Drizzle 2 tbsp salad oil over takoyaki and cook until crispy. Remove and plate.