4 large beetroot, washed but unpeeled
2 tsp table salt
2 mackerel fillets, pinboned and skinned
For the sous liquor
200ml/7fl oz white-wine vinegar
200ml/7fl oz water
100g/31/2oz demerara sugar
1/4 bunch thyme
4tsp crème fraîche
1/4 bunch tarragon, leaves picked
Preheat the oven to 180/350F/Gas4. Place the beetroot in foil and cover with the salt. Wrap and place in the oven for 90 minutes, then remove and allow to cool for 10 minutes. Using gloves, peel the skin off the beetroot and cut into 5mm-thick slices.
Place all the ingredients for the sous liquor into a saucepan and bring to the boil for five minutes. Remove and cool.
Place the mackerel fillets, skin-side down, in a shallow tray or dish. Pour over the tepid sous and allow the fish to marinate for a minimum of one hour.
To serve, dice the mackerel into chunks and arrange on the plate with the beetroot discs and a spoonful of crème fraîche. Garnish with chopped tarragon and freshly ground black pepper.Reuse content