Leek and Cheese Lasagne with Crispy Bacon Topping

The leeks and cheese go together so well, and the crispy bacon is sprinkled over the surface doubling up both as a garnish and a different texture and also as a taste enhancer. Another meal in one dish, my ideal, and a dish which can be put together easily by a fairly competent child – by this I mean one that will wash up properly after the making is finished!