Sear the minced meat in hot oil. Season with salt, pepper and paprika.
Meanwhile, clean the leek and cut into rings. Peel and roughly dice the potatoes.
Add the leek to the seared minced meat and let it brown slightly, then add the potato cubes and wait until they are also a little seared. Deglaze with the vegetable stock and cook for a quarter of an hour with the lid half closed. Season to taste with pepper and salt and thicken with the crème fraiche.
Arrange on plates and serve garnished with a spoon of crème fraiche.