Potato and Leek Soup with Mustard

Set at Pension Linden

15 minutes · Serves 4 as a light main course, with bread

a warming winter lunch

Ingredients

• 500g leeks, trimmed and thoroughly washed
• 500g floury potatoes, peeled and cut into 2cm pieces
• 25g butter
• 1 garlic clove, finely chopped
• 1 litre vegetable stock, preferably reduced salt
• 100ml single cream
• 20g Dijon mustard, about 1 tbsp plus 1 tsp
• 1 tbsp olive oil
• ¼ tsp fine salt, plus more if needed
• ¼ tsp freshly ground black pepper
• 4 thick slices of bread, to serve

Method

1. Reserve 60g of the pale green leek for the topping and cut it into fine ribbons. Dry these thoroughly. Slice the remaining 440g into thin half-moons.
2. Melt the butter in a large saucepan over a medium-low heat. Add the sliced leeks and the measured salt. Cook for 10 minutes, stirring occasionally, until soft without browning. Add the garlic and cook for 1 minute.
3. Add the potatoes and stock. Bring to a gentle boil, then lower the heat and simmer, partially covered, for 18-22 minutes, until the potatoes fall apart when pressed with a fork.
4. While the soup simmers, heat the oil in a frying pan over a medium heat. Add the dry leek ribbons in a loose layer and cook for 5-8 minutes, stirring frequently, until golden at the edges. Reduce the heat if they colour quickly. Lift onto kitchen paper; they will firm a little as they cool.
5. Take the saucepan off the heat. Mash for a rustic texture, or use a stick blender in short bursts just until smooth. Stir in the cream, mustard and pepper. Return to a low heat for 2 minutes, until hot. Taste before adding any extra salt; stocks and mustards vary. If you prefer a thinner soup, stir in hot water, 50ml at a time.
6. Divide between warm bowls, add the leek ribbons immediately before eating, and serve with bread.

Essy note: For a lactose-free version, use lactose-free butter and single cream in the same quantities. For a milder soup, begin with 10g mustard and add more after tasting.

Questions from the Kitchen

Written by Esther

Esther is a photographer and storyteller, and the founder of Essy's Essentials - a seasonal home for stories, rituals, recipes and everyday luxuries.

Published 19 September 2026

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