Whisk together the corn, zucchini, eggs and milk. Gradually stir in the sifted flour and cumin, salt and pepper.
Heat a little oil in a non-stick frying pan over medium heat. Using a tablespoon, place heaped spoonfuls of the mixture in the pan and cook in batches. Using a spatula, turn them once, until golden and cooked through.
Drain on paper towel, cover and keep warm as you cook remaining fritters.
Serve the cakes with chopped tomato, avocado, coriander leaves and sweet chili sauce.