Directions

• Peel onion and chop finely. Clean the leek, cut in half lengthways, wash thoroughly and cut into thin half rings. Sauté both in a saucepan in about three quarters of the oil over medium heat for 2-3 minutes, season with salt and pepper. Pour in the broth, bring everything to the boil with the lid closed and cook over medium heat for about 15 minutes.
• In the meantime, wash the mushrooms, rub them dry and quarter them. Wash the rosemary, shake dry, pluck off the needles and chop finely. Cut the bread into cubes of about 1 cm. Sauté the mushrooms and rosemary in the remaining oil in a pan over medium-high heat, until the liquid has evaporated, about 3 minutes. Add the bread cubes with the butter and fry for about 2 minutes. Salt the mushroom croutons and keep warm.
• Sort the spinach, rinse, and pat dry. Put a few spinach leaves aside, add the rest to the soup with the sour cream and puree everything finely. Season with salt, pepper, and lemon juice, divide between bowls and sprinkle with mushroom croutons and the reserved spinach leaves.