Delia Smith's Traditional Lasagne Al Forno

Lasagne has suffered greatly from being anglicised, factory made and served as cheap nosh, its authenticity obliterated - all the more reason to reinvent this great classic dish

1. 1

   Pre-heat the oven to gas mark 1, 275F (140C).

2. 2

   Begin by making the ragù.

3. 3

   Heat a tablespoon of the oil in your largest frying pan over a medium heat and gently fry the onion for about 10 minutes, moving it around from time to time.

4. 4

   While it is softening, chop the pancetta: roll it into a sausage shape, then, using a sharp knife, slice it lengthways into four, then slice the lengths across as finely as possible.

5. 5

   After 10 minutes is up, add this to the pan, along with the garlic, and continue cooking the whole lot for about 5 minutes.

6. 6

   Transfer this mixture to the casserole.

7. 7

   Add another tablespoon of oil to the pan, turn up the heat to its highest, then add the minced beef and brown it, breaking it up and moving it around in the pan.

8. 8

   When the beef is browned, tip it into the casserole to join the onion mixture.

9. 9

   Heap another tablespoon of oil and do exactly the same with the minced pork.

10. 10

    While the pork is browning, trim the chicken livers, rinse them under cold, running water and dry them thoroughly with kitchen paper.

11. 11

    Pull off any skin and snip out any tubes or odd bits of fat with kitchen scissors, then chop the livers minutely small.

12. 12

    When the pork is browned, transfer it to the casserole, too.

13. 13

    Heat the remaining tablespoon of oil and cook the pieces of chicken liver, adding these to the casserole as soon as they have browned nicely.

14. 14

    Remove the pan and place the casserole over the direct heat, and give everything a really good stir.

15. 15

    Add the contents of both tins of tomatoes, the tomato purée, red wine, a really good seasoning of salt and freshly milled black pepper, and about a quarter of a nutmeg, grated.

16. 16

    Stir well, then allow this to come up to a simmering point.

17. 17

    While that happens, strip the leaves from half the basil, tear them into small pieces and add them to the casserole.

18. 18

    As soon as everything is simmering, place the casserole on the centre shelf of the oven and leave it to cook slowly, without a lid, for exactly 4 hours.

19. 19

    Check after 3 hours to make sure all is well and to have a good stir.

20. 20

    When the sauce is thick, reduced, and concentrated with only a trace of liquid left in it, remove the casserole from the oven.

21. 21

    Taste to check the seasoning, then strip the remaining leaves off the basil, tear them into small pieces and stir them in.

22. 22

    To make the cream sauce, place the milk, butter, flour and some seasoning in a large, thick-based saucepan.

23. 23

    Place this over a gentle heat and whisk continuously with a balloon whisk until the sauce comes to simmering point and thickens.

24. 24

    With the heat as low as possible, continue to cook the sauce for about 10 minutes.

25. 25

    Sieve the sauce into a bowl, beat in the cream, taste and season if it needs it, and grate in another quarter of the whole nutmeg.

26. 26

    Spread about a quarter of the ragù over the base of the roasting tin (or dish).

27. 27

    Cover this with one fifth of the sauce, followed by a quarter of the mozzarella, then arrange a single layer (about 6 sheets) of the lasagne.

28. 28

    Repeat this process three more times, finishing with a final layer of sauce, then cover the whole lot with the grated Parmesan.

29. 29

    When you're ready to bake the lasagne, pop it onto the top shelf of the oven, pre-heated to gas mark 4, 350F (180C), for 45-50 minutes, or until it's bubbling and turning slightly golden on top.