Whitebait

Yes, that's a very small picture - it's a very small fish. Three inches would be a large white bait. That's so small, you eat it whole - head, tail and all. And it is truly delicious, and very good for you because all those bones give you plenty of calcium. The only downside is that it needs to be deep-fried, but in the case of whitebait, you'll only need a centimetre of oil (and plenty of wrist action). This small fish has a big history, which you can read about here.