The Daily Telegraph - Saturday - The Telegraph Magazine
Ultimate mushroom lasagne
Prep time: 25 minutes, plus infusing time Cook time: 1 hour 50 minutes
My idea of heaven. It’s based on vincisgrassi – a rich lasagne that includes prosciutto and, sometimes, chicken livers – but has no meat.
INGREDIENTS For the bechamel
– 1.2 litres whole milk
– 2 bay leaves
– ½ large onion, peeled
– 12 black peppercorns
– fresh nutmeg
– 75g butter
– 115g plain flour
– 100-200ml double cream (optional)
For the lasagne
– 20g unsalted butter,
plus extra for greasing
– 30g dried porcini
– 4½ tbsp olive oil
– 1.2kg mushrooms (a mixture of oyster, chestnut and shiitake), sliced
– 3 long shallots, finely chopped
– 2 garlic cloves, grated to a purée
– 250g fresh lasagne sheets (I use The Fresh Pasta Company’s egg lasagne sheets)
– 135g Parmesan, finely grated, or vegetarian alternative
For the bechamel, put the milk, bay leaves, onion, peppercorns and a grating of nutmeg in a pan, and heat to just below boiling. Take off the heat, leave to infuse for an hour, then strain.
Meanwhile, butter an ovenproof dish approximately 30 x 20cm and 7cm deep. Put the dried porcini in a bowl and pour in just enough boiling water to cover.
Heat one tablespoon of the oil in a large frying pan and sauté a quarter of the sliced mushrooms, getting a good colour all over them. Add a little knob of the butter for flavour. Season and continue to cook until the mushrooms have exuded their moisture and it has evaporated – any excess moisture will make your lasagne watery. Tip into a bowl. Cook the rest of the mushrooms in batches in the same way, adding each batch to the bowl.
Add the final half a tablespoon of oil to the pan and gently sauté the shallots. When they’re soft, add the garlic and cook for two minutes. Stir into the mushrooms.
Drain the porcini – reserving the liquid – and chop them. Put these in the frying pan with the reserved liquid and cook until the liquid has disappeared. Add the porcini to the rest of the mushrooms. Set aside.
Melt the butter for the bechamel in a saucepan and add the flour. Stir together until you have a ball of butter and flour. Take the pan off the heat and add the strained milk a little at a time, stirring in each addition so the mixture doesn’t go lumpy. When you have combined everything, put the pan back on the hob and heat, stirring all the time, until the mixture begins to boil and thicken. Turn the heat down a little and cook for five minutes so the sauce doesn’t taste ‘floury’. Season well and add more freshly grated nutmeg.
Add the mushrooms to the bechamel. If the sauce seems too thick, add some cream then check your seasoning.
Heat the oven to 210C / 200C fan/gas mark 7.
Cook the pasta sheets according to the packet instructions, then drain. Put a layer of sheets in the bottom of the dish, cutting them to fit; don’t overlap. Cover with a layer of sauce and scatter on some cheese. Follow with another pasta layer, a layer of sauce and a scattering of cheese.
Continue layering, keeping enough sauce to spoon over the top and a final sprinkle of cheese. Bake for 40 minutes, or until the top is brown and bubbling.
Let the dish settle, out of the oven, for about 15 minutes before serving.