Step 1

Bring to the boil 1 1/2 pints of water, add 2tsp of salt. Once the water is boiling whisk in the polenta flour; when it starts to thicken add the grated parmesan and 2oz of diced butter whisking till melted. Pour the polenta into a shallow baking tray and leave to cool.

Step 2

Blanch and deseed the tomatoes. Cut each tomato into 8 pieces. Peel and finely slice the onion. Crush the clove of garlic. Heat 1tbsp of the olive oil in a saucepan, add the sliced onion and the garlic and gently cook

Step 3

(with the pan covered) until the onion softens. Add the tomato, red wine vinegar, sugar, tomato puree and season. Stir in well and allow to stew slowly until the mixture dries out a little. It needs to cook slowly for approximately 20 minutes.

Step 4

Fillet and pin bone the mackerel. Score each fillet of mackerel and season each fillet on the meat side. Place the fillets, skin side up, on a grilling tray greased with some of the olive oil. Melt the remainder of the butter and brush this on to the skin of each mackerel fillet then slightly sprinkle them with salt.

Step 5

Cut the polenta into 3 inch diameter rounds. Place on a greased tray and brush the tops with a little of the remaining butter melted and grill with the mackerel fillets. When the mackerel has cooked the skin should be crisp and brown. The polenta will also brown slightly.

Step 6

To assemble place a round of polenta in the middle of each plate, spoon the stewed tomato onto the polenta. Lay a fillet of mackerel on top of the tomato and either put a spoon of pesto on top of the mackerel or spoon it around.