- Cut all the panini in half lengthways and slice some tomato on each of the bases.
- Take the mackerel fillets and remove the skin. Use your fingers to break up the flesh and put it into a bowl.
- Mix in the mayo and pop this fish mixture on top of the tomatoes.
- Next, lay on the rocket and finally crumble the feta over the top.
- Put the panini tops on, pop them in a panini maker and toast for 2 minutes, or until golden.