Place the eggs in a small pan, cover with cold water and slowly bring to the boil. Simmer for 7 mins. Drain the eggs then rinse in cold water. Tap the shells all over and peel away the shells.

Flake the mackerel fillets and add to the eggs with mayonnaise and seasoning to taste. Lightly mix.

Split the rolls and spread with butter. Divide the mackerel and egg mixture between the rolls and top with rocket leaves.

Wrap with clear film and chill until ready to serve.