To make the bolognese, in a large saucepan, brown the onions in the olive oil.
Add the mince meat in batches and brown all over.
Add the remaining ingredients and the water. Season generously with salt and pepper.⠀
Bring to the boil and simmer for 2 hours, half covered, until it reduces to a thick sauce, stirring every 15 minutes or so, so it doesn’t catch on the bottom. Season to taste.⠀
When ready to cook the matzagne, preheat the oven to 150C (300F).⠀
Grease a large ovenproof dish (3 litres/12 cups).⠀
Wet (not soak) the sheets of matzo so that they are damp and soft.⠀
Line the bottom of the prepared dish with the soft matzo, covering the whole base, then add a layer of sauce (bolognese or tomato) and a layer of grated cheese. Repeat again, once or twice, depending on the size of your dish. Sprinkle the top with parmesan.⠀