Ricotta and Salami Lasagne

Ingredients

• 1 onion, finely chopped
• 1 tablespoon olive oil
• 75g Henderson’s Italian Salami, chopped
• 1 carrot, diced
• 1 celery stalk, chopped
• 500g tomato pasta sauce
• 2 tablespoons chopped basil, plus extra to serve
• 375g lasagne sheets
• 400g soft ricotta
• 1 1/2 cup grated mozzarella
• 60g butter, chopped
• 1/4 cup plain flour
• 2 cups milk
• 2/3 cup grated parmesan