I'm looking for a good batter for all purpose frying, either for fish and chips, or just to coat some vegetable. I don't really want to do tempura. I want a "regular" batter.
When I fry in the past with the various flour liquid mix, I would have a finish product that is crunchy for the first two minutes, then as it cools the coating turns soggy and soft. How does the restaurants get their batter to stay crunchy even after it cools? Does it involve baking powder or baking soda?