- Add the onion, lime juice, olive oil, cumin and chilli powder to a bowl, and mix well.
- Mix in the plums, tomatoes and coriander. Cover and set aside for 5 minutes.
- Meanwhile, make three slits across the skin of each mackerel fillet.
- Grill or barbecue each mackerel fillet skin side up under a grill, or skin side down on a barbecue, for around 4 minutes. This should be enough to cook the fillet right through but if not, turn it over and cook it for 1 minute on the flesh side too.
- After warming the tortilla, add some salad leaves and a mackerel fillet. Top it with a dessertspoon of salsa and roll up.
- Serve the rest of the salsa on the side.
- Salsa works well with grilled tuna, salmon or prawns or with pork steaks.
- Mackerel are a great source of Omega 3s, as well as vitamin D.
- If taking for a picnic, cover the wrap with greaseproof paper and twist each end.