- Warm 2 tbsp of oil in a wide saucepan. Add the leeks, carrots and celery and cook gently for 10 minutes until starting to soften.
- Add the potatoes, garlic, thyme, paprika and caraway and cook for a further 2 minutes before adding the stock and bay leaves. Season lightly with salt and pepper being aware that the sauerkraut will bring some saltiness when added later. Bring to a gentle simmer and cook for 15 minutes with a lid on.
- Next, stir in the sauerkraut and cook for a final 10-15 minutes, or until the potatoes are completely tender. Taste and tweak the seasoning with salt, pepper, and a squeeze or two of lemon juice to taste.
- Heat your grill and toast the bread lightly on both sides. Spread each slice with a thin layer of mustard and then sit them on top of the soup in the pan - it may be easier to fit them in the pan if you halve them first. Top each slice generously with grated cheese and slide the pan under the grill until the cheese is bubbling. If this manoeuvre seems risky, you can grill the cheese toasts on a baking tray separately then serve them on top of your soup bowls.
- Serve to the table while still bubbling hot and ladle clumsily into wide bowls to serve. Garnish with some fresh herbs and the pot of mustard as a condiment.
This dish is all the better if you can use your own sauerkraut. For the Riverford's basic homemade recipe, click here