Red Onion Marmalade


  • 2kg red onions or regular onions
  • 4 garlic cloves
  • 140g butter
  • 4 tbsp olive oil
  • 140g golden caster sugar
  • 1 tbsp fresh thyme leaf
  • pinch of chilli flakes (optional)
  • 75cl bottle red wine
  • 350ml Biona Organic red wine vinegar
  • 200ml port


    • Halve and thinly slice the onions, then thinly slice the garlic.
    • Melt the butter with the oil in a large, heavy-based saucepan over a high heat.
    • Tip in the onions and garlic and give them a good stir so they are glossed with butter. Sprinkle over the sugar, thyme leaves, chilli flakes if using and some salt and pepper.
    • Give everything another really good stir and reduce the heat slightly. Cook uncovered for 40-50 minutes, stirring occasionally.
    • The onions are ready when all their juices have evaporated, they’re really soft and sticky and smell of sugar caramelising.
    • They should be so soft that they break when pressed against the side of the pan with a wooden spoon.
    • Slow cooking is the secret of really soft and sticky onions, so don't rush this part.
    • Pour in the wine, vinegar and port and simmer everything, still uncovered, over a high heat for 25-30 minutes, stirring every so often until the onions are a deep mahogany colour and the liquid has reduced by about two-thirds.
    • It’s done when drawing a spoon across the bottom of the pan clears a path that fills rapidly with syrupy juice.
    • Leave the onions to cool in the pan, then scoop into sterilised jars and seal. Can be eaten straight away, but keeps in the fridge for up to 3 months.

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