Sauté onion, carrot, celery, and bay leaf in oil for 6 minutes, then add garlic for 2 minutes.
Brown the beef mince, season, mix in tomato purée, and deglaze with red wine.
Add tomatoes and 400ml stock, তারপর simmer for one hour until thickened.
Preheat oven to 190°C, make a roux with butter and flour, then whisk in milk and nutmeg until thickened.
Layer one-third meat sauce, some béchamel, pasta sheets, and Parmesan in a dish.
Repeat the layers twice more, finishing with béchamel and the remaining Parmesan.
Drizzle with oil and bake for 40 minutes at 190°C until golden and bubbling.