Melt the butter in a saucepan. Stir in the flour and cook for 1-2 mins.
Take the pan off the heat and gradually stir in the milk to get a smooth cheese sauce. Return to the heat, continue stirring. Bring to the boil then simmer for 8-10 mins.
Add half the grated cheese and heat gently for 1 min, whisking until the cheeses have melted, season with nutmeg, salt and black pepper.
Put the creamed mushrooms into a bowl and combine with half the cheese.
Put half the cheese and mushrooms sauce in the bottom of an oven proof dish and pour over 1 can of ratatouille. Lay 3-4 pasta sheets over the top then repeat.
Pour the remainder of the cheese sauce over the top of the lasagne, sprinkle with the remaining Gruyere and Parmesan.
Bake in the oven for 30-40 mins. Allow to stand for 10 mins before serving.
Celebrate National Vegetarian Week from 18th-24th May 2009 www.cannedfood.co.uk www.vegsoc.org
Notes
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