Riverford Wicked Leeks
Slow-cooked red onions recipe image

Print Slow-cooked red onions

You can also use shallots or white onions for this as well, but red will give the sweetest results. Slow-cooking brings out the natural sugar in onions; use them in everything from risottos, pasta sauces and pizza toppings to soups, stocks, and stews. They also make a good accompaniment to fish and meat.


  • 1 tbsp olive oil
  • 4-5 red onions, depending on size, cut into quarters (leave the root intact so they don’t fall apart)
  • 1 tsp sugar
  • 3 tbsp red wine vinegar
  • 2 tbsp tomato purée
  • Small handful raisins
  • 1 bay leaf
  • 1 tbsp fresh thyme leaves
  • Small handful fresh parsley, chopped
  • 8 tbsp water


  1. Heat the oil in a large pan. Add the onions and fry until they have slightly coloured.
  2. Add sugar and vinegar and cook for a few minutes more. Add the tomato purée, raisins, herbs, water.
  3. Cook on a very low heat for about 40 minutes.
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