Sauté the Pancetta: Heat the olive oil in a large, heavy-bottomed pot or Dutch oven over a medium heat. Add the diced pancetta and cook for 5-7 minutes, stirring occasionally, until it's golden and crisp and has rendered its fat.

Cook the Soffritto: Add the chopped onion, carrot, and celery to the pot with the pancetta. This vegetable base is known as a 'soffritto', and cooking it properly is vital. You can learn more about its importance at BBC Good Food. Sauté for 10-12 minutes, stirring often, until the vegetables are very soft, sweet, and fragrant but not browned. Add the minced garlic and cook for another minute until you can smell it.

Brown the Mince: Increase the heat to medium-high, add the beef mince to the pot, and break it up with a wooden spoon. Cook until the meat is browned all over. Season generously with salt and pepper. Don't worry about draining the fat unless there's an excessive amount – it's all flavour!

Deglaze and Add Liquids: Pour in the red wine and scrape any browned bits from the bottom of the pot. Let it bubble away for 2-3 minutes until the alcohol smell has cooked off and the wine has mostly evaporated.

Add Milk and Simmer: Pour in the milk, stir well, and let it simmer and bubble away until it has been almost completely absorbed by the meat. I find that this step is crucial for tenderising the beef. It might look a little strange at first, but trust the process!

The Long Simmer: Stir in the tinned tomatoes, tomato purée, beef stock, bay leaf, and grated nutmeg. Bring the sauce to a gentle simmer, then reduce the heat to the lowest possible setting. Partially cover the pot with a lid and let it cook for at least 1 hour and 15 minutes, or up to 3 hours. The longer it simmers, the richer the flavour will be. Stir it every 20-30 minutes to prevent it from catching on the bottom.

Cook the Pasta: About 15 minutes before the sauce is ready, bring a large pot of salted water to a rolling boil. Add the spaghetti and cook according to the packet instructions until 'al dente' (firm to the bite).

Combine and Serve: Just before draining the pasta, scoop out a mugful of the starchy pasta water. Drain the spaghetti and return it to its pot. Remove the bay leaf from the bolognese sauce. Add a few large spoonfuls of the sauce to the spaghetti, along with a splash of the reserved pasta water. Toss everything together vigorously for a minute until the pasta is beautifully coated. Serve immediately in warm bowls, with extra sauce spooned over the top and a generous grating of fresh Parmesan cheese.