Sweet Potato and Haddock in an Onion


Sweet Potato and Haddock in an Onion

How to make Sweet Potato and Smoked Haddock in an Onion
  1. Preheat the oven to 200C/gas mark 6. Place the sweet potatoes in the oven and bake until cooked through.
  2. Place the whole onions, including the skins, in a pan of water and bring to a gentle boil. Simmer until they feel soft when you insert the tip of a knife. Remove and leave to cool.
  3. In a large pan, bring the milk, thyme, garlic and bay leaf to the boil. Simmer for 5 minutes, then remove from the heat and leave for 20 minutes to allow the flavours to infuse. Return the milk to the boil and add the haddock. Cook for 2-4 minutes depending on the thickness of the fish. Remove the pan from the heat and leave to cool.
  4. Once the onions have cooled, cut off the tops and set aside. Gently scoop out the onion flesh. Chop ¾ of the scooped out flesh from one onion and put it in a large bowl. Place the onion shells upside down to allow any juices to drain out.
  5. Scoop out the flesh from the baked sweet potatoes, mash and place in the bowl with the onion.
  6. Drain the haddock (keeping the cooking liquid). Remove the skin and any bones, flake the flesh and place in the bowl with the sweet potatoes.
  7. Remove the garlic from the milk and add to the sweet potato and haddock. Mix together with the paprika, herbs, half of the cheese and a little of the reserved milk.
  8. Reduce the oven temperature to 180°C/gas mark 4. Spoon the sweet potato mix into the onion shells and sprinkle with the remaining cheddar. Place the onions in a tray with a little water, with the top of each onion next to it. Bake in the oven for 15-20 minutes or until heated through. Place the top back on the cooked onion and serve.


  • The onions can be prepared well in advance and will last for up to two days in the fridge. If they have been refrigerated, remove them from the fridge for half hour before filling them.
  • Smoked haddock can be replaced for any other fish.
  • If serving as a main course, garnish with a few baby vegetables cooked in a little garlic, herbs and a touch of cream.



300g sweet potatoes

6 large onions

300ml milk

2 sprigs of thyme

2 garlic cloves

1 bay leaf

300g undyed smoked haddock

½tsp smoked paprika

Small bunch each of basil and parsley, chopped

100g mature cheddar cheese, grated

Salt and freshly ground black pepper, to taste


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