Slow cooker minestrone

Name: Slow cooker minestrone
Ingredients: 100g/3½oz smoked, dry-cured lardons; 2 carrots, roughly chopped; 2 sticks celery, sliced; 1 onion, roughly chopped; 2 garlic cloves, crushed; 2 sprigs fresh rosemary, needles finely chopped; 1 tsp dried thyme; 1 tbsp tomato purée; 400g/14oz can chopped plum tomatoes; 1.2 litres/2 pints good-quality chicken stock; 400g/14oz can cannellini beans in water, rinsed and drained; 50g/1¾oz spaghetti, snapped into short lengths; 100g/3½ head baby leaf or spring greens, thickly shredded; Salt and freshly ground black pepper; 2 tbsp extra virgin olive oil; 25g/1oz parmesan, grated