1.In a large bowl, combine whitebait, vinegar, garlic, oregano, chilli and pepper. Cover; refrigerate 3 hours or overnight.
2.Drain the whitebait, pat dry with absorbent paper.
3.In a large bowl, toss whitebait and flour together; season.
4.Heat vegetable oil in large saucepan; deep-fry oregano a few seconds or until crisp (be careful, oil may spit). Drain on absorbent paper.
5.Deep-fry whitebait, in batches, until browned lightly. Drain on absorbent paper. Serve topped with deep-fried oregano.