Cut the meat loaf into cubes and fry in a pan with a little fat. Cut the leek into fine rings and add to the meat loaf and fry briefly. Deglaze with broth. Stir in the cream cheese, sour cream and mustard. Add the pasta. Stir in the sauce thickener until the sauce has the desired consistency. Season to taste with salt, pepper and spices. Finally stir in a dash of vinegar so that everything tastes slightly sour.
I`ve also baked the dish with cheese several times, it tastes very good too!