Make the dipping sauce by mixing the mango chutney with the lime juice. Pour into a small bowl and set aside.
Put the flour, cayenne and grated Parmesan in a small mixing bowl and season well. Add the eggs and milk and beat until smooth.
Pour the oil into a large pan (so it's about 6cm/2in deep) and heat until a tiny piece of cauliflower sizzles when tested. Dip the cauliflower florets in the batter and then fry, in batches, for 2-3 minutes until golden, turning once or twice to brown evenly.
Drain on kitchen paper and serve with the mango dipping sauce. Eat them straight away while they're still hot and crunchy.