Tip the courgettes into a colander, sprinkle with salt and toss well. Leave for 20 mins then rinse and squeeze them between your hands to extract any water then blot on kitchen paper to dry.
Mix the courgettes with the curry powder, chilli, garlic, spring onions, thyme leaves, salt and plenty of pepper. Stir in the egg and milk, sift in the flour and baking powder, then stir again to combine.
Lightly oil a non-stick frying pan and fry heaped teaspoonfuls of the batter for 3 mins on each side. Keep warm while you use up the remaining batter – you should get 18 cakes altogether. (These can be made a day ahead up to this stage then chilled.)
To serve, heat the oven to 200C/fan 180C/gas 6. Arrange the cakes on a baking sheet and dot with a little tomato chutney and then a cube of mozzarella. Bake in the oven for 8-10 mins until hot and melted then pile onto a platter.