Sauté of octopus with a scorched white onion, garlic purée, straw potatoes and ceps

Preheat an oven to 160°C/140°C fan/gas mark 3. Place the octopus tentacles into a bowl and add the lemon zest, orange zest and olive oil. Mix thoroughly, transfer to a roasting tray, cover with foil and cook for 1 hour

Remove the foil and cook for a further 10 minutes. The octopus should now be tender – check with a skewer that it penetrates easily. Set aside to cool

Once cooled, lift out the tentacles and slice diagonally into 0.5cm-thick slices. Set aside in the fridge

For the garlic purée, place the garlic cloves into a pan with 1 litre water, bring to the boil and simmer for 5 minutes. Drain and repeat this process four more time, with fresh water each time. This removes the bitterness and astringency from the garlic

After the fifth time, place the drained garlic into a small pan, cover with the cream, season with salt and pepper and cook, covered, for 15 minutes. Transfer to a blender and blend to a smooth purée. Pass through a fine sieve, check the seasoning and set aside to cool

Next, prepare the scorched onions. Preheat the oven to 200°C/180°C fan/gas mark 6. Peel the onions and carefully trim just enough off the root so the onion will stand up securely. Do not over trim – you need to create a small fat surface but keep the root intact as much as possible. Then, cutting down to within 1cm of the root, cut vertically down the onion as if you were going to cut it in half. Turn the onion through 90° and repeat this – as if you were now going to cut into quarters. Repeat four more times, cutting through the remaining gaps to create an onion with even cuts all the way round, down to within 1cm of the root

Place the onions onto a roasting tray, spoon the olive oil over them, season lightly with salt and pepper and place into the oven for 15 minutes. They will catch a bit of colour. Baste with the oil, turn the oven down to 160°C/140°C fan/gas mark 3 and cook for a further 20 or so minutes, by which time the onion will have opened out like a flower

Season with a little more salt and pepper, baste once again with the oil and cook for a further 5 minutes. The final onion should have ‘petals’ that are black on the tips, caramelised on the edges and with a soft centre. Remove from the oven and keep warm

For the straw potatoes, peel the potato, cut into fine matchstick-sized batons and rinse under running water for 15 minutes. Drain and pat dry

Heat the vegetable oil to 150°C. Add the potatoes (in two or three batches) and cook until golden brown. Remove from the oil, drain on absorbent paper and sprinkle with salt

Place a large heavy-based frying pan over a high heat for 1 minute. Add the extra virgin olive oil and butter, allow the butter to melt and add the ceps and thyme. Season with salt and pepper and sauté until just golden. Drain in a colander to remove excess butter

To serve, place the pan back over the high heat for a minute. Add the remaining olive oil and follow with the sliced octopus. Sauté until just golden. Add the ceps back to the pan and toss to combine. Finish with the chopped parsley

Warm through the garlic purée. Place a swirl of garlic purée onto the centre of 4 warmed plates. Sit the onion on top and surround with the octopus and ceps. Garnish with some of the straw potatoes and serve the rest on the side