BBC Food - Recipes - Vegetarian Puy lentil lasagne

Ingredients

• knob of butter , for greasing and frying
• 200g/7oz Puy lentils
• 1 vegetable stock cube
• 1 tbsp garlic infused olive oil , or olive oil , for frying
• 1 onion , chopped
• 1 garlic clove, chopped
• 110g/4oz mushrooms , finely diced
• 110g/4oz leek , finely sliced
• 1 x 400g/14oz can chopped tomatoes
• sea salt
• freshly ground black pepper
• 6-9 sheets lasagne
• handful grated Parmesan (or vegetarian alternative)
• green salad , to serve
• 110g/4oz butter
• 85g/3½ oz plain flour
• 850ml/1½ pints milk
• 6 tbsp double cream
• 110g/4oz grated cheddar