Go for a dry, oaky chardonnay to accompany this hearty soup.
Dice onion. Wash the leeks, then slice into rings.
Heat oil in a large saucepan set over medium-high heat, then add the ground beef and fry until browned. Add the onion and leeks after approx. 2 min. Cook for approx. 5 min. more. Deglaze with vegetable stock, then let simmer for approx. 10 min.
Stir in the cheese and let melt. Stir in crème fraîche and boil again briefly.
Season the soup with salt, pepper, nutmeg, and some lemon zest to taste. Serve with a slice of fresh bread and enjoy!