Salmon and sweet potato gratin recipe

Prep 15 minutes, cook 25-30 minutes

For a fish dish with a bit of a twist, try this salmon and sweet potato gratin recipe from Discover Great Veg. It takes just a few minutes to prep and cooks all in one tray – an easy mid-week meal with limited washing up. Good news all round!

Salmon is a rich source of the omega-3 fatty acid DHA – an essential nutrient for good brain health and function. Plus it’s also high in protein, helping to support our muscles and protect bone health.

This gratin recipe uses sweet potato, but can easily be swapped out for butternut squash or potatoes. Experimenting with flavours can help to make this dish your own, so don’t be afraid to use what you have in the cupboard.

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  • 4 skinless salmon fillets, diced (500g)
  • 200g sliced Cavolo Nero
  • 1 tbsp oil
  • 250g leeks, sliced
  • 200ml crème fraîche
  • 2 sweet potatoes, approx 500g, thinly sliced
  • 2 tbsp chopped chives


  1. Preheat the oven to 200oC, 180oC fan, gas mark 6.
  2. Blanch the salmon and cavolo nero in boiling water for four minutes, and drain.
  3. Meanwhile, heat half the oil in a frying pan and fry the leek for three minutes. Add the salmon and cavolo nero, stir in the crème fraîche and cook for one minutes. Season and transfer to a heatproof serving dish.
  4. Toss together the sweet potatoes, chives and remaining oil. Season and scatter over the salmon mixture. Bake for 25-30 minutes until the sweet potatoes are golden and tender.