Arrange the courgettes, peppers, tomatoes, and onion in the air fryer. Drizzle with the olive oil and season with salt and pepper.
Cook for 10-15 minutes or until the vegetables are tender and beginning to caramelise.
Mix the balsamic vinegar, olive oil and Dijon mustard together to make the dressing.
To serve, arrange the mixed salad leaves onto a plate and top with the cooked vegetables. Sprinkle with blue cheese, scallions, olives, pine nuts and fresh basil leaves before serving with the vinaigrette dressing.