To make the ragù alla bolognese, heat the olive oil in a large heavy-based stockpot over medium heat. Add the onion and cook for 2 minutes. Add the carrot and celery, then cook, stirring, until the onion is soft (approximately 3 minutes). Add the beef and pork mince (ground meat) to the stockpot with vegetables. Cook, stirring with a wooden spoon, breaking up any lumps until the mince is lightly browned all over. Add the red wine (or white wine) and cook for about 5 minutes or until the wine has reduced. Stir in the Italian passata, tomato paste and water. Season with salt to taste and bring to the boil. Reduce the heat to low and simmer for approximately 1 hour or until the ragù has reduced to your required consistency. Stir the ragù alla bolognese occasionally so that the sauce does not stick to the pot and burn, then remove from the heat. Add more water to the ragù alla bolognese, as needed to keep the sauce lovely and moist.

Preheat the oven to 180°C conventional oven/ 160°C fan-forced (350° Fahrenheit/Gas 4). Grease a baking dish with butter or margarine.

To make the Besciamella sauce, melt the butter in a medium-sized saucepan over medium heat until foaming. Add the flour and stir with a wooden spoon to form a smooth paste (a roux). Allow the flour and butter mixture to cook for a minute (but do not allow it to brown). Remove from the heat. Slowly pour the cold milk into the roux, stirring constantly, until the mixture is smooth. Add the bay leaf and return to medium heat. Cook, stirring with the wooden spoon until the Besciamella comes to the boil and thickens (approximately 10 minutes). Remove from heat. Season with salt to taste and stir in freshly grated nutmeg. Set aside to cool slightly.

Remove the dried lasagne sheets from the packet.

Ladle ragù alla bolognese and besciamella sauce to just cover the base of the baking dish. Cover with a layer of pasta sheets that overlap slightly. Spoon ragù alla bolognese where the pasta overlaps. Ladle 1/3 of the ragù alla bolognese over the pasta sheets, using the back of a ladle to press it down and level it. Spread 1/3 of the besciamella sauce over the ragù alla bolognese. Sprinkle 1/2 of the mozzarella cheese. Continue layering with the pasta sheets, ragù alla bolognese, besciamella sauce and mozzarella cheese. Finish with a layer of pasta, ragù alla bolognese, besciamella sauce and Parmigiano Reggiano sprinkled to cover the lasagne.

Bake in a preheated oven for 30 minutes. Remove from the oven. To confirm that the lasagne is cooked, insert a knife in the centre of the baking dish and hold it there for a few seconds – if the knife blade is hot, the lasagne is ready. Leave to rest for a minimum of 10 minutes before serving.

Cut the traditional meat lasagne into 6 portions and serve – buon appetito.