Combine vinegar and sugar in a small glass bowl and stir until sugar has dissolved. Add onion and stir well. Stand for 15 minutes. Drain.
Meanwhile, heat oil in a small non stick frypan over medium heat. Add Edgell Corn Kernels and cook for 1 minute until lightly charred.
Top tortillas with lettuce, carrot and corn. Top with John West Tuna and pickled onions.
Garnish with coriander. Squeeze over lime juice and serve with aioli.
For an added chilli hit, garnish tacos with thinly sliced red chillies before serving.