While oil is heating over medium high heat, make vegetable mixture. In a large mixing bowl, mix all the vegetables, eggs, flour, soy sauce, bonito and dashi.
When oil is hot drop vegetable mixture into pan flatening it into a small pancake shape. This needs to be no thicker than 1/3 of an inch so that it has time to cook through. Fit as many as you can in your pan without overcrowding or dropping the temperature too much. Once browned on one side, flip and brown the other side. Remove to drain on a paper towel.
For the sauce, mix the mayo, ketchup and worcestershire sauce together and then drizzle over the hot pancakes. Top with the dried seaweed and serve.