Gill Meller’s Cornish New potatoes with bay, lemon, garlic, mackerel fillets and green herb sauce

Skill level
Preparation Time
20 minutes
Cooking Time
35 - 40 minutes
Serves 2-3

“The Cornish New potato season coincides perfectly with the beginning of the mackerel season, so it seems fitting to serve these two wonderful seasonal treats together in this all-in-one tray bake. There’s no need to par boil the potatoes, just give them a scrub and you're ready to go.” - Gill Meller. Recipe created for Seasonal Spuds, by Gill Meller.


  • 1.2 kg of Cornish New potatoes
  • 2 fresh mackerel, filleted
  • Zest of 1 lemon
  • 6–8 bay leaves
  • 2 small or one larger red onion, thinly sliced
  • 3 tbls of olive oil

For the green herb sauce

  • 1 handful of flat-leaf parsley, leaves picked
  • 1 small handful of mint
  • 1 tbsp capers
  • 2 tsp mustard
  • 1 small garlic clove, grated
  • 3–4 salted anchovy fillets in oil
  • 1 tbsp cider vinegar
  • 3 tbsp extra-virgin olive oil, plus extra to loosen, if necessary
  • Sea salt and freshly ground black pepper


  1. 1Start by making the green herb sauce, place the parsley and mint on a board and use a nice sharp knife to chop it all up. Add the capers, mustard and grated garlic and carry on chopping until it’s all fairly fine.
  2. 2Spoon into a bowl and add the vinegar and olive oil and season with salt and pepper to taste. It should have a loose-ish consistency, a bit like a dressing, so add a splash more oil or a tiny dash of water if it’s a bit thick.
  3. 3Scrub the New potatoes to remove any grit or soil. Halve the big ones, then arrange them over a large baking tray in a single layer. Trickle over 2 Tbls of olive oil and season them well with salt and pepper.
  4. 4Place the potatoes into a hot oven, about 200°C, and roast them for 15 to 20 minutes. Remove the tray from the oven and scatter over the bay leaves, sliced red onions and lemon zest. Turn everything together and return to the oven for a further 12–15 minutes or until the potatoes are tender and golden.
  5. 5Cut the mackerel fillets in half, trickle them with the remaining olive oil and season them all over with a little salt and pepper.
  6. 6Place the fish on top of the potatoes and return to the oven for about 5 minutes; this should be enough to cook the mackerel through.
  7. 7Remove the tray from the oven and dot all over with the green herb sauce. Serve at once with a nice crisp green salad.