Ingredient

Lasagne

A good lasagne is a thick ragù, a properly seasoned béchamel and pasta, layered so the pasta has enough moisture to cook and not so much that the whole thing floods the plate. Watery lasagne is the commonest failure, and it is always a sauce problem.

Why it goes watery

Three sources of water, and usually all three at once. A ragù that was not reduced enough. A béchamel that is too thin. And vegetables — courgette, spinach, mushrooms, aubergine — that were not cooked and drained before they went in.

The dish is sealed under a layer of cheese in a hot oven, so none of that water can escape. Whatever moisture goes in is still there when you cut it.

So the rule is that every component should look slightly too thick going in. A ragù stiff enough to hold a spoon-mark, a béchamel that coats heavily, and vegetables cooked until they have given up their water and browned a little.

Building it

1. Make the ragù and reduce it until thick — see bolognese. It should not be soupy.
2. Make a béchamel slightly thicker than you would for a sauce, and season it properly with salt and nutmeg. See cheese sauce.
3. Start with a thin layer of ragù on the base so the first sheets do not stick and burn.
4. Then alternate: pasta, ragù, béchamel, a little parmesan. Do not overload any single layer — thin layers give a lasagne that holds together.
5. Finish with pasta, then a generous layer of béchamel, then cheese. The top béchamel layer is what browns.
6. Bake at around 180°C for 40 minutes or so, until bubbling at the edges and deeply browned on top. Cover with foil if the top colours early.
7. Rest it for at least 20 minutes before cutting. This is not optional — a lasagne cut straight from the oven collapses.

The pasta question

Dried no-cook sheets

Convenient, and they need enough sauce moisture to hydrate. If your sauces are thick, dip the sheets briefly in hot water first.

Dried sheets, pre-boiled

More reliable, less brittle, and easier to fit. Boil for a couple of minutes, no more.

Fresh sheets

The best texture by a distance. No pre-cooking needed.

Fresh egg pasta made at home

Better still, and the traditional Bolognese version uses spinach-green sheets.

Layers

Four to six is usual. More thin layers beats fewer thick ones.

Common mistakes

• Cutting it hot. Twenty minutes of resting is what lets it set enough to serve in squares.
• Too much sauce per layer. It slides apart.
• Under-seasoned béchamel. Bland béchamel makes the whole dish bland — it is a large proportion of what you are eating.
• Ricotta instead of béchamel. Common outside Italy, and it weeps unless drained thoroughly first.
• Wet vegetables. Cook and drain everything.
• Not enough sauce at the very edges. Exposed pasta at the corners goes hard and inedible.

Common questions