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Cheesy onion soup with bubbling Gruyère croutons drizzled with Wilson's Foods Extra Virgin Olive Oil

Cheesy Onion Soup

This is proper autumn comfort food — sweet slow-cooked onions in a rich stock, finished with oozing, bubbling cheese croutons on top. The kind of soup that makes you glad it's getting cold.
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Prep Time 15 minutes
Cook Time 1 hour 15 minutes
Total Time 1 hour 30 minutes
Servings: 6
Course: Main Course, Starter
Cuisine: French, South African
Ingredients Method Notes

Ingredients
  

  • 250 g Butter
  • 30 ml Wilson's Foods Extra Virgin Olive Oil plus extra to finish
  • 1.5 kg Mixed onions red and white, peeled and finely sliced
  • 3-4 cloves Garlic peeled and finely sliced
  • 2 litres Good quality beef or vegetable stock
  • 1 Splash Worcestershire sauce
  • Sea salt and freshly cracked black pepper
  • 6-8 slices Good quality bread about 2cm thick
  • 15 g Butter for the croutons
  • 5 ml Dijon mustard
  • 150 g Gruyère or mature Cheddar grated (or a mix of both)

Method
 

  1. Melt the butter with the Extra Virgin Olive Oil in a large, heavy-based ovenproof pot over medium-high heat. Add the garlic and stir for a minute, then tip in all the onions. Season well with salt and pepper and stir to combine.
  2. Turn the heat down to low, place a cartouche (a piece of baking paper cut to fit the pot) directly on top of the onions, and cook slowly for 45–50 minutes, stirring occasionally, until deeply golden and sweet. Don't rush this step — the slow caramelisation is where all the flavour comes from.
  3. Remove the cartouche, pour in the stock and bring to a simmer. Add a splash of Worcestershire sauce, taste and adjust the seasoning. Simmer gently for 15 minutes to let the flavours come together.
  4. While the soup simmers, preheat your grill to maximum. Toast the bread slices on both sides until golden. Spread one side of each slice with a little butter and a smear of Dijon mustard.
  5. Slice, grate or crumble the cheese generously over the mustard side of each toast. Cut the croutons into large pieces and lay them directly on top of the hot soup in the pot, pushing them down slightly so they soak up a little of the broth.
  6. Grate over a little extra cheese and add another shake of Worcestershire sauce. Place the pot under the hot grill for 5–10 minutes until the cheese is melted, bubbling and golden. Watch it carefully — it goes from golden to burnt quickly.
  7. Ladle into bowls and finish each serving with a drizzle of Wilson's Foods Extra Virgin Olive Oil. Serve immediately.

Notes

The cartouche (a round of baking paper placed directly on the onions) keeps the moisture in and helps the onions caramelise without catching. Don't skip it — it makes a real difference. For the cheese, a mix of Gruyère and mature Cheddar gives you the best of both — Gruyère for meltability and depth, Cheddar for sharpness. The soup improves significantly overnight, so make it a day ahead if you can and grill the croutons fresh just before serving.