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French onion soup toastie
Makes: 2
Prep time: 20 minsTotal time: 
Recipe photograph by Rob Streeter
French onion soup toastie
All the cheesy comfort and caramelised flavours of a French onion soup in toastie form
Makes: 2
Prep time: 20 minsTotal time:
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Nutritional information (per serving)
Calories
684Kcal
Fat
41gr
Saturates
19gr
Carbs
39gr
Sugars
11gr
Fibre
6gr
Protein
26gr
Salt
2gr
Helen Graves
Helen Graves, also known as @foodstories on Instagram, is a food writer and the co-founder and editor of fire-cooking magazine Pit.
See more of Helen Graves’s recipes
Helen Graves
Helen Graves, also known as @foodstories on Instagram, is a food writer and the co-founder and editor of fire-cooking magazine Pit.
See more of Helen Graves’s recipes
Ingredients
- 20g butter
- 2 medium onions, sliced thinly
- 75g Gruyère or vegetarian alternative, grated coarsely
- 75g ready-grated mozzarella
- 4 slices Pain de Campagne or sourdough bread
- 2 tbsp mayonnaise
- Marmite, to taste
Step by step
Get ahead
The caramelised onions keep in the fridge for 3-4 days.
- Melt the butter in a large nonstick frying pan and gently cook the onions with a large pinch of salt until they’re soft and caramelised, around 30 minutes, stirring often; remove from the heat.
- Combine the grated cheeses in a bowl. Spread 2 pieces of bread with mayonnaise, then turn one over and spread with Marmite on the other side. Top with a layer of onions, then the cheese mixture and the second slice of bread, mayo side outwards. Repeat for the second sandwich.
- Wipe out the frying pan with kitchen paper then heat up on the hob. Add both sandwiches. Cook over a medium heat for 3-4 minutes each side, weighing the sandwiches down as they cook with something heavy (such as another pan, with a couple of tins of beans inside as extra weight), so that they have maximum heat contact. They should be golden brown, crisp, and molten inside.