Preheat the oven to 190C/Gas 5/fan oven 170C. Heat the oil in a non-stick pan, add the pork and quickly fry until starting to become brown and crumbly. Add the onion, celery, rosemary and wine and bring to the boil. Cover and gently cook for 10 minutes, until softened.
Add the stock, tomato purée, canned tomatoes, and season. Stir well, then bring to the boil, cover and simmer for 30 minutes by which time it will be nicely pulpy. Blend the cornflour to a paste with a few drops of water, then add to the pan and cook briefly until slightly thickened. Remove from the heat.
Tip the Quark into a bowl. Give it a stir, then stir in the milk, nutmeg, seasoning.
Brush a 1.4 litre/2½ pint oblong dish with a little oil. Spoon a third of the meat over the base, then cover with 2 sheets of lasagne, breaking them to fit, if necessary. Try to avoid overlapping. Spread with a third of the sauce, a little parmesan, then 2 more sheets of lasagne. Repeat layers twice more, omitting the last layer of lasagne and finishing with the sauce.
Sprinkle with remaining parmesan and bake for 30-35 minutes, until golden and tender.