Cooking Notes: in pan, then about 4hr on Low
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- 75 g (3oz) butter
- 700 g (1 1/2lb) onions, thinly sliced
- 3 garlic cloves, crushed
- 1 Tbsp. plain flour
- 200 ml (7fl oz) dry white wine
- 1 l (1 3/4 pints) hot vegetable stock
- 1 bay leaf
- Few fresh thyme sprigs
- Few parsley sprigs
- 1 small baguette, cut into slices 1cm (1/2in) thick
- 50 g (2oz) Gruyère or Cheddar cheese, grated
- Step 1
Melt the butter in a large pan and gently fry the onion over a very low heat, stirring frequently, until very soft and golden brown (about 30min). Add the garlic and flour and cook for a further 1min, stirring, continuously.
- Step 2
Pour in the wine, bring to the boil and bubble until the wine is reduced in volume by half. Add the stock, then tie the bay leaf, thyme and parsley sprigs together with a piece of string to make a bouquet garni and add to the pan with some seasoning. Bring to the boil then carefully transfer mixture to a slow cooker, cover and cook on Low for 3-4hr until the onions are meltingly tender.
- Step 3
When ready to serve, preheat the grill to medium. Lightly toast the slices of baguette on both sides. Reheat the soup and adjust the seasoning. Discard the bouquet garni.
- Step 4
Divide the soup among four ovenproof soup bowls. Float two or three slices of toast on each portion and sprinkle thickly with the grated cheese. Stand the bowls under the hot grill until the cheese has melted and turned golden brown. Serve immediately.
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Per Serving:
- Calories: 438
- Total carbs: 45 g
- Total fat: 48 g
- Saturated fat: 21 g
- Protein: 11 g

The GH Kitchen Team are Good Housekeeping’s resident recipe developers and all-round food obsessives. GH Kitchen Director Sarah Akhurst is our resident hosting pro and loves nothing more than putting on a foodie feast for friends. Our GH Kitchen Manager Linzi Pucino is our very own Italian food expert (originally hailing from the North East of Scotland!) and can be found working her way through midweek recipes that cover all bases, from haggis to ragu! Our Kitchen Editor Nadine Brown loves digging into the stories behind her favourite foods and enjoys applying her eclectic tastes to more modern, flavour-forward recipes - just don't give her too much chilli! Our Junior Food Content Produce Frankie Prichard combines a love of beautiful presentation and flavour-led, seasonal cooking in her recipe development, along with a passion for bringing people together through food. With a wealth of professional kitchen experience between them, they’re dedicated to ensuring every Good Housekeeping recipe is the best it can be, so you can trust they’ll work every single time
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