For the pickled cucumber, bring the vinegar, sugar, bay and juniper berries to the boil in a pan and allow to cool. Submerge the cucumber in the liquor, season and set aside

To make the horseradish cream, whisk the double cream and grated horseradish until softly whipped, season with lemon juice, salt and pepper. Continue whisking until slightly firmer. Place mixture in a piping bag

Preheat the oven to 180°C/Gas mark 4. Remove the skin from the mackerel. Bake the skin between parchment paper brushed with a little olive oil for 8 minutes or until the skin has coloured nicely, allow to cool. Remove any bones down the centre of the fish fillets and dice the flesh into 1cm cubes

Arrange the white radish in the centre of 4 plates (12cm diameter approximately). Arrange the red radish slices onto 4 x 12cm circles of parchment paper that have been brushed with little olive oil. Overlap each slice to form a full circle, repeat the process working into the centre until the parchment circles are covered

Take the cubes of raw mackerel and dress with a little lime and lemon juice, olive oil and seasoning. Pipe a layer of horseradish cream over the white radish then, place the dressed mackerel on top. Finally turn the red radish over and gently place over the fish. Remove the parchment and finish with the drained cucumber and shards of crispy skin