Superb squash soup with the best Parmesan croutons

INGREDIENTS

• olive oil
• 16 fresh sage leaves
• 2 red onions, peeled and chopped
• 2 sticks celery, trimmed and chopped
• 2 carrots, peeled and chopped
• 4 cloves garlic, peeled and chopped
• 2 sprigs fresh rosemary, leaves picked
• ½ - 1 fresh red chilli, to taste, deseeded and finely chopped
• sea salt
• freshly ground black pepper
• 2 kg butternut squash, onion squash or musque de Provence, halved, deseeded and cut into chunks
• 2 litres organic chicken or vegetable stock
• extra virgin olive oil
• 16 slices ciabatta bread
• 1 block Parmesan cheese, for grating