Slow Cooker French Onion Soup

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4:15

Serves 4

Medium

Let the slow cooker do all the work and enjoy a deliciously rich and cosy French soup after a long day.

This slow cooker French onion soup recipe takes all the classic ingredients, so you can immerse yourself in an incredibly comforting and hearty dish on a cold night. Top with a cheesy crouton for extra goodness.

Content image
Ingredients image

What you'll need...

  • 800g white onions, thinly sliced
  • 50g unsalted butter
  • 1 ½ tbsp caster sugar
  • 1 bay leaf
  • 3 thyme sprigs
  • 1 tbsp plain flour
  • 2 stock cubes, beef (or vegetable to make it vegetarian)
  • 3 tbsp Worcestershire sauce
  • 2 tbsp balsamic vinegar
  • 1 white baguette, sliced
  • 70g gruyere cheese, grated

Method

  1. Preheat your slow cooker. Add the sliced onions, unsalted butter, caster sugar, thyme and bay leaf into the pot. Cover with the lid and cook on high for 3 hours or until the onions are soft and golden. 

  2. Stir in the plain flour then pour in the stock, balsamic vinegar and Worcestershire sauce. Cover and cook for 1 hour. 

  3. Preheat the grill to high and cut the baguette into slices. Grill until golden, top with gruyere then grill again until the cheese is bubbling.  

  4. Serve the soup into individual bowls and top each with a warm, cheesy crouton. Season with salt and pepper to taste. 

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Shop the tools you will need

Secondary image for Professional X50 Contour Santoku Knife Main image for Professional X50 Contour Santoku Knife

£26

Secondary image for Digital Slow Cooker Main image for Digital Slow Cooker

£59

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£179

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£39

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