Leek and Potato Soup in the style of Paul Bocuse

Ingredients

• 500 g Leeks (white and green parts, washed and sliced into 2‑3 mm strips)
• 200 g Potatoes (peeled and diced into small cubes)
• 100 g Unsalted butter (cut into pieces)
• 120 g Thick crème fraîche (from Normandy, to add at the end of cooking)
• 1 L Mineral water (chlorine-free, for a purer taste)
• 12 g Fine salt (to adjust to taste)
• au goût Freshly ground black pepper (to grind at the time of adding)
• 30 g Grated Gruyère (for garnish)
• 30 g Croutons (for crunch, homemade or store-bought)

Instructions

1. Prepare the vegetables

   Thoroughly wash the leeks to remove sand, cut the white and green parts into very thin strips (2‑3 mm). Peel the potatoes and cut them into small dice about 1 cm.

   Time: PT10M

2. Melt the butter and sweat the leeks

   Place 100 g of butter in the pot, melt over low heat without letting it brown. Add the sliced leeks, cover lightly and let them sweat gently for 5 minutes, stirring regularly.

   Time: PT5M

   Temperature: feu doux

3. Add the potatoes

   Stir the potato dice into the pot, mix and let them brown lightly for 3 minutes.

   Time: PT3M

   Temperature: feu moyen

4. Add water, salt and pepper

   Add 1 L of mineral water, 12 g of salt and a generous turn of black pepper. Bring to a boil uncovered.

   Time: PT5M

   Temperature: feu vif

5. Cook the soup

   Reduce heat to medium and let simmer uncovered for 15 minutes, until the potatoes are tender.

   Time: PT15M

   Temperature: feu moyen

6. Incorporate the crème fraîche and blend

   Turn heat down to minimum, add the thick crème fraîche (120 g) and stir gently. Using a whisk, lightly mash the potatoes to achieve a creamy texture without making the soup completely smooth.

   Time: PT5M

   Temperature: feu doux

7. Season and serve

   Taste the soup, adjust seasoning if needed. Ladle the soup into shallow bowls, sprinkle with grated Gruyère and croutons for crunch.

   Time: PT4M

Nutrition Facts

Calories

270

Protein

8 g

Carbohydrates

40 g

Fat

20 g

Fiber

5 g

Ingredient Substitutions

• Instead of Leeks: shallots, chives
• Instead of Potatoes: Yukon Gold potatoes, floury potatoes
• Instead of Unsalted butter: margarine, vegetable oil (for a different flavor)
• Instead of Thick crème fraîche: sour cream, thick cream mixed with a splash of lemon
• Instead of Mineral water: filtered tap water
• Instead of Fine salt: sea salt, kosher salt
• Instead of Freshly ground black pepper: white pepper
• Instead of Grated Gruyère: Emmental, Comté
• Instead of Croutons: toasted bread cubes

Equipment Needed

• Large pot or saucepan
• Wooden spoon or spatula
• Chef's knife
• Cutting board
• Measuring jug or pitcher
• Whisk
• Ladle (optional)
• Cheese grater (optional)

Critical Steps — Do Not Skip

• Sweat the leeks gently without browning.
• Do not skim the soup to retain the butter and rich flavor.
• Add the crème fraîche off high heat to prevent it from separating.

Chef Tips from the Video

• Use mineral or spring water for a purer taste.
• Do not skim the soup; the butter adds body and flavor.
• A drizzle of truffle oil at the end adds a luxurious note.

Troubleshooting

Storage

Refrigerator: Store in an airtight container for 3 to 4 days.

Freezer: Can be frozen for 1 to 2 months; thaw slowly in the refrigerator then reheat over low heat.

Room temperature: Do not leave at room temperature for more than 2 hours.

Make-Ahead Tips

• The soup stores very well and gains flavor when it rests overnight in the refrigerator.
• Add the crème fraîche just before reheating to prevent it from separating.