- 25g (1oz) dried porcini mushrooms
- 25g (1oz) butter
- 3 garlic cloves, crushed
- 1kg (2lb 4oz) mixed mushrooms
- 3tbsp dry white wine
- 300g (10oz) spinach, wilted and seasoned
- 150g (5oz) fresh lasagne sheets
- for the béchamel sauce
- 75g (3oz) butter
- 75g (3oz) plain flour
- 700ml (1¼pt) whole milk
- 100g (4oz) Parmesan, plus extra for grating
Preheat oven to 200 C, 180 C fan, 400 F, gas 6. For the sauce, melt butter in a pan; stir in flour. Cook for 1 min; turn heat down, slowly pour in milk while whisking. Cook, stirring, until you have a thick, smooth sauce. Remove from heat, stir in Parmesan and season. Put clingfilm on surface of sauce.
Soak porcinis in hot water for 15 mins; drain. Melt butter in a frying pan; cook garlic for 2 mins. Increase heat; throw in all mushrooms, mix, season, sauté for 5 mins. Add wine; allow the excess liquid to evaporate. When mushrooms have softened slightly, remove from heat, place in a sieve and drain off liquid.
In an ovenproof dish, make 2 layers of: mushrooms, then spinach, lasagne and sauce. Sprinkle top with Parmesan; bake in top third of oven for 20 mins. Remove from oven; rest for 10 mins before serving. You can make the sauce the day before and refrigerate, or freeze the made-up lasagne before cooking.