1. You can use either already prepared lasagne sheet from the store or make three coloured lasagne sheets yourself if you have a pasta machine. To make the green sheets: parboil the spinach until they soften, drain well, then blend them. Add the flour and three eggs. Knead until you get a smooth dough. Cover with cling film and allow to rest at least for 15 minutes. To make the yellow sheets: in a bowl add the flour and eggs and knead until you get a smooth dough. Cover with cling film and allow to rest at least for 15 minutes. To make the red sheets: in a bowl add the flour, eggs and tomato paste and knead until you get a smooth dough. Cover with cling film and allow to rest at least for 15 minutes. Using a pasta machine roll the thin-layer lasagne sheets, sprinkle with some flour and allow to dry briefly.

2. Make the béchamel sauce. In a saucepan melt the butter, add the flour and stir until smooth. Pour the milk while continuing stirring until smooth and thickens. Sprinkle the grated nutmeg, pepper and salt. The consistency of the sauce should be thick enough not to drop quickly from the spoon.

3. Make the Bolognese sauce. Pour the olive oil into a pot, add the sliced carrot, onion and peeled celery stalk. Fry on a low heat until the onion browns, then add the beef mince, season with salt and mix well. Increase the heat and fry stirring constantly. When the brown sticky layer forms on the bottom of a pot, pour the red wine in and allow it to evaporate. Add the tomato paste and leave to braise for about 20 minutes. Add the rosemary and garlic. Season with some salt if needed.

4. Mix together both the sauces. Pour the mixed sauce into a baking tin, spread the mozzarella cheese and Prosciutto Cotto ham over the sauces, and Parmesan cheese on top, then cover with lasagne sheets. Repeat at least 4 times until all the sauce is finished.