Boil new potatoes until cooked but still firm, allow to cool.
Finely chop spring onion, capers and gherkins.
Slice the potatoes and place in a bowl, add spring onions, capers and gherkins to the potatoes.
Add the mayonnaise until you reach the desired consistency and mix.
Halve the ciabatta length ways and drizzle with olive oil.
Now place the bread face down on a griddle pan until toasted.
Time to season the mackerel. Pour a little olive oil into a hot frying pan and place the mackerel skin side down in the pan and cook until crispy (around 3-4 mins) then turn once cooking the other side for about a minute.
Now place the potato mix on the toasted ciabatta and top with mackerel.
Add a little squeeze of lemon over the top and serve.