Heat olive oil in a heavy-bottomed pot over medium heat. Add the diced vegetables and sauté until softened and golden, about 8-10 minutes – this is your soffritto, the aromatic foundation of great ragù. Add pancetta and cook until the fat renders and edges crisp slightly.

Increase heat to medium-high and add ground beef, breaking it apart with a wooden spoon. Cook until deeply browned, about 10-12 minutes – don’t rush this step as the browning creates incredible depth of flavor. Season with salt and pepper.

Pour in white wine and let it bubble vigorously until mostly evaporated, scraping up any browned bits from the bottom. Add passata, torn basil leaves, and beef stock. Bring to a gentle simmer, then reduce heat to the lowest setting

Here’s where patience becomes your secret ingredient: let the ragù simmer uncovered for 3-4 hours, stirring occasionally. During the last 30 minutes, gradually add the milk, which will create an incredibly silky texture. The finished ragù should coat a spoon and have a rich, deep color.

Blanch spinach in boiling salted water for 2 minutes, then plunge into ice water. Squeeze out every drop of water – this is crucial for preventing soggy pasta. Purée the spinach until smooth.

Create a well with flour on a clean work surface. Crack eggs into the center, add spinach purée and olive oil. Using a fork, gradually incorporate flour until a shaggy dough forms. Knead for 8-10 minutes until smooth and elastic. Wrap in plastic and rest for 30 minutes.

Roll pasta through a machine or with a rolling pin until paper-thin – you should almost be able to read through it. Cut into rectangles that fit your baking dish.

Melt butter in a heavy saucepan over medium heat. Whisk in flour and cook for 2 minutes to eliminate raw flour taste – this is your roux. Gradually whisk in warm milk, ensuring no lumps form. Cook, whisking constantly, until thickened enough to coat the back of a spoon, about 8-10 minutes. Season with nutmeg, salt, and white pepper.

Preheat oven to 375°F (190°C). Butter a 9×13-inch baking dish generously.

Bring a large pot of salted water to boil. Cook pasta sheets for 30-60 seconds until just tender – they’ll finish cooking in the oven. Lay on clean kitchen towels.

Spread a thin layer of béchamel on the dish bottom, followed by a light coating of ragù. Layer pasta sheets, ensuring they don’t overlap. Spread ragù evenly, then béchamel, and sprinkle with Parmigiano-Reggiano. Repeat for 6-7 layers total.

For the final layer, use only béchamel and a generous amount of cheese – no ragù on top, as tradition dictates. Dot with small pieces of butter.

Bake covered with foil for 45 minutes, then uncovered for 15 minutes until golden and bubbling at edges. Let rest 15 minutes before cutting – this allows the layers to set properly.