1. Mix the courgettes, salad onions and flour together; crack in the eggs and beat well to combine. Season, then fold into the ricotta, not doing too thorough a job, so you are left with lots of ricotta lumps.
2. Cook the fritters in 3 batches: heat 1 tbsp oil in a large non-stick frying pan over a medium heat and drop in 2 heaped tbsp of batter per fritter. Cook for 3 minutes on each side, or until golden.
3. Meanwhile, combine all the ingredients for the salsa and season. Serve the fritters with the salsa alongside.