- Preheat the grill to medium.
- Drizzle a little of the oil from the can of mackerel over the baguette slices. Place under the grill for a few minutes (garlic and oil side up), until lightly toasted (make sure they don’t burn).
- Combine the tomatoes, onion, parsley and garlic. Add lemon juice to taste and the remaining oil from the canned mackerel. Break the mackerel fillets into small pieces.
- Top the toasted baguette slices with the tomato mixture, followed by the mackerel. Finish with a grind of black pepper, and serve with the lemon wedges.