- 4 baby cucumbers, skin only
- 1 tbsp green tea powder
- 1 Japanese radish, washed and peeled
- 75ml/2½fl oz beetroot juice
- 250ml/9fl oz pomace oil (or a light olive oil)
- 25ml/1fl oz white wine vinegar
- ½ tsp salt
- 7.5g/⅓oz caster sugar
- 25ml/1fl oz honey
- 4 sprigs thyme, leaves picked and finely chopped
- 1 garlic clove, finely chopped or grated
- 4 red beetroot
- 4 baby cucumbers, peel used for garnish (from above)
- 5g salt
- 5g sugar
- 1 tbsp lemon juice
- 200g/7oz Cornish sea salt
- 125g/4½oz sugar
- 7.5g/⅓oz coriander seeds, crushed
- 7.5g/⅓oz white peppercorns, crushed
- 4 very fresh good-quality mackerel fillets, pin-boned and cut lengthways into two
- 4 limes, zest and juice only
- 1 large cucumber, peel only
- 50ml/2fl oz pomace oil (or a light olive oil)
- For the garnish, peel all the baby cucumbers and dry the skin out in a dehydrator (alternatively place in an oven set at the lowest temperature for a few hours or leave overnight in a warm airing cupboard).
- When the cucumber skins have fully dried, blend to a fine powder in a food processor. Mix equal quantities of the cucumber powder with the green tea powder and set aside.
- For the beetroot, add the oil, vinegar, salt, sugar and honey to a blender (or a thermo mixer) and mix until emulsified. Add the thyme and garlic and set aside.
- Use a mandoline to slice the beetroot, then place in a bowl. Add the oil mixture, cover and leave to marinade for two hours.
- For the baby cucumbers, use a chef's blow-torch to scorch the peeled baby cucumbers until evenly coloured. Place in a sous vide bag along with the remaining ingredients.
- Seal the bag and transfer to a water bath (according to manufacturer's instructions) to cook for 20 minutes.
- For the mackerel, in a bowl combine all the ingredients, except the mackerel, lime zest and lime juice, and mix thoroughly.
- Place the mackerel fillets flesh-side up onto a tray, then evenly pack the salt mixture onto the flesh and set aside for 25 minutes.
- For the cucumber oil, peel the cucumber and blanch the skin. Drain well, then add to a food processor with the pomace oil and blend to a deep green oil.
- For the mackerel, brush the salt off the mackerel and discard.
- Use a chef's blow torch to cook the mackerel (alternatively cook them under a very hot grill for a few minutes). Season with sea salt, lime juice and zest.
- For the garnish, using a mandoline, cut the radish into slices. Then cut into strips and dip into the beetroot juice very briefly just before serving.
- To serve, place two pieces of mackerel onto the centre of each plate and top with a few slices of marinated beetroot. Remove the marinated cucumber from the bag and cut into 2cm/1in thick slices, then place the slices around the mackerel. Pile the Japanese radish at the end of the mackerel. Dot a little cucumber oil around the plate then dust with the green tea powder.