The secret to any good French onion soup is to cook the onions really slowly, letting their sugars caramelise for a depth that contrasts beautifully with the Marmite.

Serve alongside a homemade French baguette, or check out more warming soup recipes such as our classic French onion soup, leek and potato soup, celery soup and butternut squash soup.


  • 2 tbsp vegetable oil
  • 4 large onions, thinly sliced
  • 4 cloves garlic, crushed
  • 1 tbsp Marmite
  • a few sprigs thyme
  • 2 litres vegetable stock
  • 1 tbsp soft light brown sugar
  • 1 tbsp balsamic vinegar


  • 4 slices sourdough
  • 2 tsp Marmite
  • 75g gruyère (or veggie alternative), finely grated
  • a few sprigs thyme, leaves picked


  • STEP 1

    Heat the oil in a large pan and cook the onions with a large pinch of salt over a low-medium heat for 20 minutes, stirring occasionally. Turn down the heat to low and cook for 40 minutes until the onions are really caramelised and jammy. Stir in the garlic and cook for 5 minutes to soften, then add the Marmite, thyme and stock and bring to a simmer. Cook gently for 15 minutes, then season with the sugar, vinegar and some salt and pepper.

  • STEP 2

    Heat the grill to high. Toast the bread on both sides, then spread over the Marmite, sprinkle over the cheese and thyme, and grill until the cheese is bubbling.

  • STEP 3

    Ladle the soup into bowls, top with the Marmite toppers and scatter with a few more thyme leaves.

Discover more of our Marmite recipes

Marmite Pie


Adam Bush Chef Portrait
Adam BushDeputy food editor

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