Mix together the rosemary, sugar and salt

Coat the fillets well on both sides and lay out on a flat baking sheet or tray covered with cling film.

Place in the fridge for 30-45 minutes to cure

Remove from the fridge, rinse each fillet well and wrap tightly in food quality cling film.

Return the fillets to the fridge - they will firm up in 30 minutes or so but can be left for a few hours if necessary

Heat the oven to 180C

Put the tomatoes on a baking tray drizzled with a little of the olive oil.

After the tomatoes have cooked for 5 minutes or so, heat the rest of the oil in an ovenproof skillet

Fry the fish, service side down for 2 minutes, then turn and cook for a further minute

Place the skillet in the oven and cook for a further 5 minutes or so until the fish is opaque and flaky

Serve garnished with parsley