Peel onion and garlic and chop finely. Peel and slice the carrots, clean and wash the leek and cut into pieces.
Heat oil in a pan. Fry the tartar until crumbly. Add onion and garlic, sauté. Add the vegetables and fry for about 5 minutes. Stir in tomato paste. Season with salt, pepper and paprika.
Heat the butter in a saucepan and sweat the flour in it. Add ¼ l of water and the milk. Stir in the broth, simmer for 2 - 3 minutes. Season to taste with lemon juice, salt, pepper, sugar and nutmeg.
Pour approx. 1/3 of the sauce into a baking dish. Put the pasta on top. Spread the minced vegetable mixture over the pasta, pour the remaining sauce in between. Baked in a preheated oven at 175 ° C for about 15 minutes.