Wash the leek and cut into thin rings. Fry the mince in olive oil and season with salt, pepper and paprika powder. Add leek and fry for a few minutes. Add 2 cans of tomato paste and sauté. Pour some stock into the now empty cans and shake.
This way you have used the last of the tomato paste. Then add from the cans to the pan. Bring to a simmer.
At the same time, put on the spaghetti and cook until al dente.
When the spaghetti is ready, fold the herbs into the sauce and serve immediately with the spaghetti. If you like, sprinkle the dish with freshly shaved Parmesan. If you like, you can use red wine instead of the stock.