- 20g (3/4oz) butter
- 2 onions, finely chopped
- 3 garlic cloves, crushed
- 750g (1lb 10oz) button mushrooms, halved
- 15g (1/2oz) dried porcini mushrooms soaked in 150ml (1/4pt) boiling water
- 2tsp fresh thyme leaves
- 200g (7oz) thin slices prosciutto, for example, Parma ham
- 200g (7oz) grated mozzarella
- 8 sheets fresh lasagne
- 2tbsp breadcrumbs
- 2tbsp Parmesan, grated
- For the béchamel:
- 100g (4oz) butter
- 100g (4oz) plain flour
- 850ml (11/2pt) semi-skimmed milk, heated
- 3tbsp Parmesan, grated
Preheat the oven to 180 C, 160 C fan, 350 F, gas 4. Melt the butter in a frying pan and cook the onions until soft. Add the garlic for a few minutes then the button mushrooms, drained porcini and thyme, and cook for 15 minutes or until slightly soft. Season well.
To make the béchamel, melt the butter and stir in the flour. Mix well and cook for a few minutes then stir in the milk, whisking until thickened. Season. Stir in the Parmesan.
Lay a third of the mushrooms, prosciutto and mozzarella in the base of a 2-litre (31/2pt) baking dish, followed by a layer of pasta and a third of the béchamel. Repeat, finishing with a layer of sauce. Sprinkle the breadcrumbs and Parmesan over the top and bake for 45 minutes or until browned and bubbling.